I think it's more of a "maybe, it depends, we can't tell by the topic alone."
I guess some assets wouldn't be a problem, like some armor, weaponry, etc., but I think more comprehensive mods would be a bigger issue, like remaking a village, a level or something else that very distinctly Witcheresque.
Borrowing assets is one thing, partially remaking a game is something different altogether.
And I think a mod must be distinctively not too much a (part of) The Witcher 2.