I looked at all the confirmed returning Pokemon so far and arranged the most relevant ones into categories based on how I think they might perform in VGC 2020. Thoughts?

Likely to have a very strong presence:
Arcanine
Snorlax
Tyranitar
Scrafty
Aegislash
Likely to have a strong presence:
Hitmontop
Ludicolo
Pelipper
Milotic
Gigalith
Ferrothorn
Hydreigon
Likely to be relevant:
Gyarados
Gardevoir
Gastrodon
Bronzong
Whimsicott
Gothitelle
Bisharp
Mandibuzz
May see some play:
Gengar
Torkoal
Drifblim (if a reliable terrain setter becomes available)
Togekiss(may be good Follow me support)
Lucario
Conkeldurr
Musharna
Meowstic
https://www.serebii.net/swordshield/galarpokedex.shtml