Ignore this guide, Dekita's SQL Mod Menu allows you to unlock a lot of stuff, including all looks / collections.

Get it here[www.nexusmods.com]

Hogwarts Legacy was such an amazing journey to me that I found myself already itching to replay it with a different house, but I had already invested colossal effort on my first playthrough collecting gear and unlocking new gear/cosmetics through challenges. After expending some effort looking for any kind of unlocker or save editor, I finally found a crude workaround that allows you to transfer your cosmetic outfit between characters with the help of nathdev's amazing Dual Dresser[www.nexusmods.com] mod on Nexusmods.

1) Download Dual Dresser[www.nexusmods.com] from Nexus Mods

• 1.1 Install Dual Dresser by extracting it to Steam\steamapps\common\HogwartsLegacy\Phoenix\Content\Paks\~mods
  
• 1.2 if the ~mods folder doesn't exist, create it and extract Dual Dresser there.

2) Download Blueprint Apparate Modloader[www.nexusmods.com]

• 2.1 Same as above, extract this to your ~mods folder.

*OPTIONAL*

• Install Dek's Apparate UI mod[www.nexusmods.com], this adds a nice and intuitive UI for Blueprint Apparate Modloader. It's not necessary, and the functionality is the same, but this custom UI makes it far more intuitive.

3) After you do the above, go in the game, hit he F8 key. A menu will appear, in this menu, type "DualDresser" (CASE SENSITIVE) and hit enter. The mod will now be loaded and ready to use.

4) Press F6 to have Dual Dresser's UI appear, it has two outfit options; outdoors and indoors. You can dress your character to any outfit of your liking, then save it to either slot by clicking save. This will save the cosmetic look of your character, not the actual gear they're wearing. You can load this custom outfit at any time you want by clicking "load". The idea of this mod is that it saves the player the time of switching into and out of school uniform when venturing outside the castle and returning to it, expediting the process to only two clicks.

5) Save the outfit you want on Dual Dresser, if you load any other character on any other save, you will be able to load this outfit on other characters, even if you haven't unlocked those items on the other save.

And that's it, hope this helped!