Title says most of it, just predict what Mons the GLs so far will have, preferably using Pokémon likely or confirmed to be available. Genuine predictions, not wants.

Available Pokémon so far: https://www.serebii.net/swordshield/galarpokedex.shtml

Info:

Milo:
>Grass
>2 Pokemon
>Probably 1st Gym
>Ace is a Level 19 Dynamax Eldegoss

Nessa:
>Water
>3 Pokemon
>Probably 2nd Gym
>Ace is a Level 24 Dynamax Drednaw
>Goldeen in demo but number of Pokémon and Level was inconsistent with in-game screenshots

Bea:
>Fighting
>Unknown Pokemon and Gym number
>Ace not confirmed but has a Hitmontop of an unknown level
>Sword Only, Allister's counterpart

Allister:
>Ghost
>Unknown Pokemon and Gym number
>Ace not confirmed but has a Mimikyu of an unknown level
>Shield Only, Bea's counterpart