Here's the full list of unusual miscs (not quickswitch glitch, ones that will always be miscs) that are level 100 [this list will NEVER change unless
some new private backpacks are found (which has happened with about 8 different miscs since this guide was initially created), some of these items are deleted, or some are glitched into existence/miscs are added officially as unusuals]:
Unfortuantely, none of the very limited backpack/shirt/shoe items have a level 100 unusual variant.

To view ALL available unusual miscs (including quickswitch), here's my other guide: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2551034734

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Haunted Ghosts Virtual Viewfinder - 4117381882
Blizzardy Storm Virtual Viewfinder - 3778021140
Stormy Storm Virtual Viewfinder - 4117381882
Disco Beat Down Virtual Viewfinder - 3355957424
Disco Beat Down Virtual Viewfinder - 2365294169
Unfortunately no other all-class misc has level 100 versions.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Orbiting Planets HazMat Headcase - 1181666307
Orbiting Planets HazMat Headcase - 1178763562
Orbiting Fire HazMat Headcase - 1114430299
Steaming HazMat Headcase - 1048759610
Smoking HazMat Headcase - 968739285
Despite there being only one multi-class, but not all class misc (being the HazMat Headcase wearable by pyro and sniper), there is the same amount of unusual multi-class miscs as all-class miscs as unfortunately only one of the 4 all-class miscs has any level 100 variants.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Strange Orbiting Planets Bonk Boy - 3319957442
Strange Orbiting Planets Bonk Boy - 632665647
Strange Orbiting Planets Bonk Boy - 840586533
Strange Vivid Plasma Bonk Boy - 1712652206
Strange Flaming Lantern Bonk Boy - 1196470924
Strange Bubbling Bonk Boy - 1053585909
Stormy Storm Bonk Boy - 1035456898
Bubbling Bonk Boy - 883400844
Green Energy Professional Killstreak Bonk Boy - 536171083
Any other misc effects wanted at level 100 will rely on the all-class miscs/quickswitch glitch.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Searing Plasma Exquisite Rack - 3040673431
Aces High Exquisite Rack - 3001928418
Dead Presidents Exquisite Rack - 2469167294
Disco Beat Down Exquisite Rack - 2203599599
Terror-Watt Exquisite Rack - 1838885186
Stormy Storm Exquisite Rack - 1518153255
Blizzardy Storm Exquisite Rack - 930296124
Vivid Plasma Exquisite Rack - 421877671
Vivid Plasma Exquisite Rack - 264953378
Bubbling Soldier's Stash - 1280147681
Nuts n' Bolts Soldier's Stash - 1096692142
Green Confetti Soldier's Stash - 281576594
Scorching Flames Soldier's Stash - 276973183
Searing Plasma Soldier's Stash - 199513057
Purple Confetti Soldier's Stash - 150041575
Despite not having the most unusual misc variants, the soldier does have the most regionless miscs (all of these are regionless)

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Anti-Freeze Pyromancer's Mask - 2332090223
Terror-Watt Pyromancer's Mask - 2276206027
Power Surge Pyromancer's Mask - 1649489983
Overclocked Pyromancer's Mask - 1648994897
Bubbling Pyromancer's Mask - 1085292256
Stormy Storm Pyromancer's Mask - 756837426
Stormy Storm Pyromancer's Mask - 524264269
Green Confetti Pyromancer's Mask - 278934167
Purple Energy Pyromancer's Mask - 256966709
Sunbeams Pyromancer's Mask - 251919096
Green Confetti Pyromancer's Mask - 224030190
Green Energy Pyromancer's Mask - 211727310
Disco Beat Down Pyromancer's Mask - 3293354602
Dead Presidents Pyromancer's Mask - 2664086460
Only pyro-specific unusual misc.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
There are no demoman unusual miscs outside of quickswitch miscs.
Unfortunately for level 100 collectors, this means he can only have a maximum of 2 effects, as the only all-class regionless misc (antlers) has no unusual level 100 variants.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Molten Mallard Large Luchadore - 3292202956
Kill-a-Watt Large Luchadore - 2731329683
Disco Beat Down Large Luchadore - 2317652440
Orbiting Fire Large Luchadore - 621684051
Green Confetti Large Luchadore - 452225254
Purple Confetti Large Luchadore - 358044641
The heavy has the only level 100 misc version of a molten mallard unusual.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Morning Glory Brainiac Hairpiece - 3281041640
Miami Nights Brainiac Hairpiece - 2248944502
Terror-Watt Brainiac Hairpiece - 2129144326
Dead Presidents Brainiac Hairpiece - 1877916248
Nuts n' Bolts Brainiac Hairpiece - 1770478667
Orbiting Planets Brainiac Hairpiece - 1434087159
Stormy 13th Hour Brainiac Hairpiece - 1237192270
Nuts n' Bolts Mining Light - 1186387284
Nuts n' Bolts Mining Light - 819861316
Blizzardy Storm Mining Light - 803212740
Nuts n' Bolts Mining Light - 723604739
Scorching Flames Mining Light - 657095041
Stormy Storm Mining Light - 591095621
Eerie Orbiting Fire Mining Light - 550120224
Purple Energy Mining Light - 371072316
Burning Flames Mining Light - 156860094
The Unusual Pencil Pusher is ALWAYS level 10, so all 410 of them are technically max level if that's what you're searching for instead of a pure level 100 inventory, technically giving engineer the most max-level unusual miscs.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Cloud 9 Blighted Beak - 4999306503
Anti-Freeze Blighted Beak - 2272334551
Dead Presidents Blighted Beak - 1792978959
Blizzardy Storm Blighted Beak - 1530717932
Nuts n' Bolts Blighted Beak - 1101541582
Purple Confetti Blighted Beak - 269798502
Circling Peace Sign Blighted Beak - 249580550
Massed Flies Blighted Beak - 237500734
Green Energy Das Hazmattenhatten - 5173560125
Dead Presidents Das Hazmattenhatten - 3278888150
The Das Hazmattenhatten has a pitiful two level 100 variants, but is also your only option for green/purple energy.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Strange Electrostatic Villain's Veil - 1689330371
Strange Smoking Villain's Veil - 1472502701
Orbiting Fire Villain's Veil - 1073034543
Morning Glory Master's Yellow Belt - 3460777559
Cloud 9 Master's Yellow Belt - 3338158649
Orbiting Fire Master's Yellow Belt - 1422617569
Nuts n' Bolts Master's Yellow Belt - 1332474360
Steaming Master's Yellow Belt - 1191340027
Circling TF Logo Master's Yellow Belt - 333649967
Circling TF Logo Master's Yellow Belt - 306895127
Haunted Ghosts Master's Yellow Belt - 282366983
Circling Heart Master's Yellow Belt - 236879153
Haunted Ghosts Master's Yellow Belt - 182477170
Hellfire Soldered Sensei - 2048045043
Electrostatic Soldered Sensei - 2008566363
The sniper has some of the best level-100 misc effects available, such as hellfire, hanted ghosts, and morning glory. He is also one of the two classes who can wear the only unusual multi-class misc that isn't all class.

Item Name (left) - Item Id (right) [https://backpack.tf/item/(insert item id here)]
Smoking Noh Mercy - 454703915
Massed Flies Noh Mercy - 279326865
The Ooze Le Party Phantom - 3124323508
Sulphurous Le Party Phantom - 1712824850
Stormy Storm Le Party Phantom - 1604096142
Steaming Le Party Phantom - 899865366
Bubbling Le Party Phantom - 631538447
Purple Confetti Le Party Phantom - 279749368
Searing Plasma Le Party Phantom - 208056083
People tend to forget that the Noh Mercy was ever unusual.