@Oleh: Thanks for merging the PR. Hopefully you'll update GNU Elpa soon.
@Thien-Thi Thanks for fixing this quick.
I confirm ucs-names to be happy once again in both aa2u and counsel.
Closing this bug.
PS: @Thien-Thi: Strangely, I just noticed your reply here[1], but I never got that email in my inbox.