Dear Sébastien,
I read your posting with big interest since I'm looking for my ancestors from Crimea. Even though none of the names are familiar to me, I have a comment. Why you say "ukrainian"? Crimea became a part of Ukraine in 1954; in 19th century it was a part of Russia.
https://en.wikipedia.org/wiki/Crimea
Regards,
Jane Liss
New York
Looking for TEMCHIN, Finkel from Kerch, Odessa, Pinsk (Poland), Vilno (Vilnius) (Lithuania)