I've had Sims 4 for XBox One with 2 DLCs for a while. But I want to play it on the computer without buying the game and the DLCs again. I don't care about the progress of the game.
Is that somehow possible?
No.
No, as far as I know, this is unfortunately not possible.
No of course not.
The manufacturers earn from selling the games on different platforms. So you can't avoid a new purchase.
Microsoft's Play Anywhere is an exception. Just check online which games are supported there. The prerequisite is the purchase of a digital PC version.
Pity.