Naively, you can click on any individual note and change which voice that particular note is in by clicking on the voice label you want (details on how to do that are in https://musescore.org/en/handbook/3/voices#change-voice).
You can even exchange the voices of (two voices' worth of) notes by selecting the range you want to exchange voices of, going to the menu bar, and finding which voices you want to exchange in the resulting dropdown menus (further details in https://musescore.org/en/handbook/3/voices#exchange-voices).
This may hit snags if the note you want to swap in is a different note length than at least one note in the equivalent place in the voice you want to swap that note into, such as swapped-in notes displacing swapped-out notes or the notes refusing to swap in the first place. I'm afraid I'll have to defer to Creynders and his answer (copy and paste notes back and forth, or essentially do that by committing single notes to memory and deleting and adding them yourself) if you encounter those snags.
If you want to preserve note starts and possibly nothing else whenever you hit such a snag, you may need to edit notes in the voice you're swapping notes into to fit in the notes you're swapping out. For example, in order to successfully swap in the third note you want, a dotted 32nd note trying to displace the latter portion of a 16th note, I'll have to turn that 16th note into a 64th note.
Even if you want to preserve all note starts and note lengths when transferring that dotted 32nd note, you have to resort to hacks (with their own readability issues) such as replacing that 16th note with a 64th note tied to a dotted 32nd note, then swapping that dotted 32nd note in.