So having an idea for "characters in different game", I kinda had ideas about Warhammer Fantasy, mostly Cubicle 7 version.
Note: I know the game lore and mechanic won't fare well with Critical Role, especially interracial relations, but this is just my idea.
Vex and Vax: High Elves from Shadowlands, probably Shadow Warriors or who lived out in the woods with their father being Lothern merchant (Half Elf don't exist, so maybe issue can being treated as outsiders by inner Kingdoms for association with Malekith's rebellion and ruthlessness towards Dark Elf even by their standards).
Keyleth: High Elf Mage specializing in Beast or Wood Elf magic user.
Grog: Dwarf Slayer (maybe backstory being suggesting not killing Elves during an encounter with Vex and Vax in Old World on sight causing him to become a Slayer) or an Ogre Mercnary (but with more eating than drinking).
Pike: no Gnome, so maybe Warrior of Sigmar or Halfling Priestess.
Scanlan: same as Pike; Halfling Entertainer (Minstrel if he is human or Elf)
Percy: He would be treated as least strange since firearms are widespread (expensive, but average Warhammer humans have seen a pistol), either Noble or Engineer from Nuln.
Also no Tiberius for both lore and production reasons.