Common in WEST GREEK
Artamis (Ἄρταμις) for Artemis except in Cretan.

DORIC
Factions: Syracuse (Corinth), Taras (Sparta), Selinous (Megara Hyblaea, Megara).
Other cities: Gela (Rhodes, Crete), Megara Hyblaia (Megara), Akragas (Gela), Heraklea (Taras + Ionians from Siris), Akrai (Syracuse), Kamarina (Syracuse until 552, Gela after 461), Helorus? (Syracuse?)

Corinthian
Ϙϙ (qoppa) disappeared in the 1st half of the 5th c.
eu (ευ) from e+o contraction (ε+ο).
Apellon (Ἀπέλλων) from Apollo.
Ϝϝ (digamma) retained in all positions.
nt (ντ) from lt (λτ), nth (νθ) from lth (λθ).
Personal names in -en (ήν) for -on (-ων); c.f. Ἀρχήν (Archen) vs. Ἄρχων (Archon).
Spelling of lengthened ε is E or EI (different from ε or η), and of lengthened ο is ou.
rr (ρρ) from rs (ρσ)
Several morphological differences with masculine -ᾱς stems.

Megarian
Ϝϝ (digamma) retained word-initially in 5th cent.
nt (ντ) from lt (λτ), nth (νθ) from lth (λθ), possibly np (νπ) from lp (λπ).
rr (ρρ) from rs (ρσ)
Spelling of lengthened ε is E (different from ε or η) or ει, and of lengthened ο is O (different from ο) or ou.
Possible interchange of ι and υ in words.

Argolic
Ϙϙ (qoppa) likely disappeared in the 1st half of the 5th c.
Spelling of lengthened ε is η and ει and ῑ, and of lengthened ο is ω and ου.
Sometimes ι from ε before other vowels (usually -a and -o), c.f. θιός (thios) from θέος (theos) in Argos and Epidauros, but otherwise usually ε.
Original long diphthongs lost the second element (βωυς>βῶς vs Attic βοῦς).
ο from εο before ντ.
Some ablaut stuff that might not be important.
Ϝϝ (digamma) retained in all positions.
Consonantal ι as ιι.
/h/ was very weak, and sometimes left out of spelling.
Intervocallic σ>h.
Some assimilation of aspirates?
Transposition of ρ (ῥόπτον [ropton] from ῥόπτρον [roptron]).
nt (ντ) from lt (λτ), nth (νθ) from lth (λθ).
σσ from ττ like Ionic.
...
long list, tbc...

Laconian
Spelling of lengthened ε is η, and of lengthened ο is ω.
Sometimes ι from ε before other vowels (usually -a and -o) except when the ε was once followed by an intervocallic digamma, c.f. (thios) θιός from (theos) θέος
Intervocallic σ>h, later lost, e.g. Ελευhύνια (Eleuhynia) from Ελευσίνια (Eleusinia).
Possible interchange of ι and υ, influenced by previous ευ or the suffix συνη, e.g. Ελευhύνια (Eleuhynia) from Ελευσίνια (Eleusinia).
Some ablaut stuff that gives Ποhοιδάν (Pohoidan) from Ποσειδάων (Poseidaon).
Possible change of τ to σ.
More ablaut stuff that gives Ἀπέλλων (Apellon) from Ἀπόλλων (Apollon)
Ϝϝ (digamma) retained initially until ~400 BCE, intervocalically retained very early but likely lost in the 3rd quarter of the 5th century besides archaisms.
Some different forms of verbs.
Ϙϙ (qoppa) completely absent.

Tarantine


Heraclean
...

Rhodian
Ϙϙ (qoppa) retained late.
...

Cretan
Ϙϙ (qoppa) retained late.
...

NORTH WEST GREEK

...

Bibliography

• A Selection of Greek Historical Inscriptions to the End of the Fifth Century B.C., ed. by Russell Meiggs and David Lewis (Oxford: Oxford University Press, 1969).
  
• C.D. Buck, The Greek Dialects, BCP Edition (Bristol: Bristol Classical Press, 1998).
  
• L. H. Jeffery, The Local Scripts of Archaic Greece, Oxford Monographs on Classical Archaeology (Oxford: Oxford University Press, 1961).
  
• Roger D. Woodward, Greek Writing from Knossos to Homer (New York: Oxford University Press, 1997).