Yes, at least some were produced. I own the Princess Luna plush & have seen a couple other ponies several years back. Multi-pulti is a Russian company & I’m not sure if these MLP plushes were ever exported widely during release. I purchased my Luna on eBay from a Russian seller several years ago & currently eBay doesn’t permit Russian sellers on their platform for obvious reasons.
I can tell you that I find my plush very cute. Her paper tag has a 2013 copyright, but the plush tag attached to her back leg has a 2015 copyright. She also sings a my little pony song in Russian (I assume it’s there version of the g4 theme song) and her materials seem to be on par with the mlp Ty plushies released in the US.
I found posts on Equestria Daily & MLP merch in February 2016 showing off some of the mlp plushies that multi-pulti would be releasing, but it didn’t say anything about where they would be sold.
Don’t give up they are out there, but between sanctions & probably being out of production they will be hard to find.