So back when SM2 came out I bought the Xbox Series X/S gold edition, but now I own a PC and want to play it on that. Obviously, the one I bought is for Xbox consoles, but if I buy the base game for my PC will I be able to link my progression through the PROS account? Even keep the gold edition "status" that has the DLC colors/skins/etc?

You should be able to, I think anyway. As long as you link your pros account to your steam it should work in theory. 

Hello, PROS will only transfer saves, but not the DLC content. If you own the Gold edition on Xbox and you transfer your save to PC, you will only keep your non-DLC progress unlocked. If you wish to keep your DLC content, you'll have to own the Gold Edition on PC as well.