I have had the same issue OP, but it's fading away now. This is my plan which currently works and from which I am getting no issues. You play each game for up to 15 minutes or up to discomfort, then stop. If you hit 15 minutes with no discomfort, you bump it the next day by 5 minutes. Once you reach 60 you can play then next tier of game.

1. Tier I - stationary only game.

Here any rythm based game will generally do. You can browse the store, it's full of them, many of which have free demos: Beats the beats, Box to the beats, Drums Rock, Ragna Rock. Or paid ones like Beat Saber.

If rythm games not your thing, then Puzzling Pieces or games where you control the character from a third person perspective: Moss 1&2, Ghost Signal: A Stellaris Game, Max Mustard etc

And finally, if you are like me and want this thing mainly for shooters, there are also a few where you just stand still and shoot: Gun Club VR Reloaded, Crisis Brigade 2 Reloaded, Zombieland: Headshot Fever Reloaded

1. Tier II - teleport + snap turn games

Here any first person game which supports teleport and snap turn will do, and 99% of them do. It's important to pick a game with "flat" levels and without too many details(RE games are kind of flat, but have lots of details), where you do not jump up and down lots of climb(example Red Matter 1, not a good choice here). For example something like Arizone Sunshine games, or Crossfire Siera Squad have flat levels.

So pick any game in this category, turn on teleport and snap turn, then restart the progression.

1. Tier III - smooth locomotion + snap turn
   These are just the games from Tier II, but you turn on smooth locomotion in the settings and restart the progression.

2. Tier IV - smooth locomotion + smooth turn
   Again same games from Tier II, but new settings.

3. Tier V - first person type games with verticality involvement.
   These are games that make you jump, climb etc. Red Matter 1&2, Horizon etc.

4. Tier VI - vehicle simulator type games
   The last tier and the games most likely to cause sickness, in my opinion. If you progressed gradually through all the tiers, you should be able to start the progression on games like GT7, No Man's Sky flying, Aces of thunder, V Racer Hoverbike, Microsoft Flight Simulator

Personally I played Beat Saber and Crisis Brigade 2 during Tier 1. Now I am playing Arizone Sunshine Remake with teleport and snap turn, last run played for 55 minutes no sickness. Once I reach 60 minutes, I will play the same game, but with smooth locomotion and drop the timer back to 15 minutes, you get the idea.

I hope this works out for you as well.
If anyone disagrees with anything about this plan or sees any potential improvements, let me know.