So all of this is just based on what we've seen from Legion so far so you know they might surprise us in the same way they did with Boba.
Initial Release:
Republic
- Obi-Wan Kenobi
- Clone Troopers, likely with Z6 and a Rocket Launcher as Heavies
- AT-RT, likely very similar to the Rebel variant if not the same
- TX-130 Saber Tank
CIS
- General Grevious
- B1 Battledroids, likely with
- STAP, maybe like a speeder bike but without the mandatory movement?
- AAT
Second 'Wave'
Republic
- Anakin Skywalker
- Cold Assault Clone Trooper, Galactic Marines, or Phase II Clone Troopers
CIS
- Count Dooku
- B2 Battledroids, likely with the Rocket Arm and the shot gun configuration from the original Battlefront games or a jet pack version that helps make the group more mobile
Third 'Wave'
Republic
- Ahsoka, as an operative
- ARC Troopers, Quad Gun and maybe the rifle from the Republic Commando game or duel weilding blaster pistols.
CIS
- Ventruss, likely as a commander though possibly as an operative
- Droid Commandos,
Forth 'Wave'
Republic
- BARC Speeder Bike
CIS
- Dwarf Spider Droid
Fifth 'Wave'
Republic
- Mace Windu
- Possibly Jet Troopers, though I could see those being thrown in with Plo Koon when he is added
CIS
- Possibly Wat Tambor (due to Ryloth Campaign) or Kalani if Ventruss is a Operative, or if she is a Commander then likely Jango Fett or Cad Bane as an operative
- Droideka, likely with the Sniper Droideka maybe even deep cut into legends with the Mk2
Sixth 'Wave' - Personal Wave
Republic
- Generic Clone Commander, Clone Technician (Clone with receiver pack), FX Series Medical Droid or AZ Medical Droid, R2 Astromech though I guess they could give them a WED droid instead if they didn't want R2 getting mixed up.
CIS
- OOM Battle Droid Commander, B1 Technician (B1 with receiver pack), Medical droid could maybe be the EV series, not positive on their repair droids maybe either a WED or GNK Droid.

