Is that meaning that game will appear in GOG soon?

I want to try Wolcen, and just saw it in Wolcen GOG Wishlist.

No, it doesn’t mean anything. Wolcen was on the store for ages as indev. It was then removed being “too difficult for devs to maintain two platforms”. So take that anyway you want, I see it as they weren’t bothered and were more interested in drm.