You can't do it. You need to unland them and bring them to your court.

Fun fact, I've learned how to diablerize Caine by studying pieces of forbidden knowledge devs hide in tooltips over things you can and can not click.

Put yourself in an army, and travel the army to that persons location

Oh I didn't even know you could put yourself in an army! I'll keep in mind, thanks man =)

Well, if they are your vassal you could raise an army right in their barony, skipping travel. Also, you could force them to be knight/faris/champion. Raising army puts them into location where your army is.

Still, no cure for being landed other than revocation.

引用自 Das Boot：

You can't do it. You need to unland them and bring them to your court.

lol u can, u go with troops