I am pretty sure Larian holds the rights to its game, editor and any content made through this editor and content created with in-game resources.
So, no, thankfully you cannot sell your mods.

If Larian would allow it, they'd instantly kill D:OS' future modding community.
And, really, people wanting to sell their mods are plain greedy.

Now asking for donations would be fine in my opinion. I would never do this myself, because I'm not greedy, but if you published a great mod and people want to donate something for your hard work, well, who's stopping them.