[2023] Getting back in - confused about standalone v steam for VR

Hi o7

Sorry for the noob Q although I bought the game when it first came out (years ago), got 200 hours in it and lost interest after the mining nerf, now looking to try it again.

I fly in VR.

I bought it in standalone mode and IIRC got it somehow linked up to steam - not entirely sure why, perhaps I needed that in order to play VR. I think I remember when loading the game even I had to do it from standalone launcher, or perhaps did it on steam then it loaded up the launcher. Honestly can't remember.

Anyway I looked at the standalone launcher today and I see I have "legacy horizons" whatever that is and so I updated it, but not the latest horizons I guess? So I'm a bit confused. Because there's another Horizons game that I haven't installed yet. From my google searching I understand the horizons legacy is a closed system and I need the latest one or progress won't carry over.

Then I see on steam I can update it there too, so I'm doing that as well as I type. But now I think I may as well get the latest version (Odyssey) instead.

So my Qs are:

1) Do I buy the Odyssey version through steam or do I have to buy it through Frontier as I bought the original standalone version (and then got linked to steam later)?

2) Will my current achievements carry over? Because I read that if you play legacy horizons achievements won't carry over as it's a different fork.

As I say I play VR which is why I think I need to have the steam access.