Translation:I do not move next to these people.
If you're moving house (which költözik implies), 'beside' sounds a little awkward. It's usually coupled with 'next to', since you're moving into the next house, I'd say.
Does this sentence even make sense? I would have said "Ezek az emberek mellé én nem költözöm."
You have to assimilate the postposition to the pronoun ez in the same way that you do the case suffixes. For example, in this house is ebben a házban, not ez a házban. Similarly you have to say e mellé a ház mellé = (to) beside this house and ezek mellé az emberek mellé = (to) beside these people