I have had success merging my communities. I ran PS5 and then was given ownership of PlayStation. I posted locked vote posts in each community with two comments. One for yes, one for no. Only upvotes on the comments were counted as some instances disable downvotes. Each community overwhelming voted to merge under c/PlayStation. Since then it has been smooth sailing.
I left the previous community open (with a pinned post explaining the merge) for people to use if they want to, but so far everyone migrated no problem.
Currently I am only subbed here since I don’t want double posts, but I am for the merge and will easily just sub to the new community.