So a lot of people have been thinking that Eevee's Z-Move is going to be some big buff to the Pokemon, but that is not at all the case. What everyone seems to be forgetting is that every single Pokemon can use Z-Moves. Of course in comparison to the current meta a huge stat seems like a big deal, but it won't be when every Pokemon can run essentially a kill move.

I believe people are failing to realize this because Eevee's Z-Move is the only one that we know what it really does. Which is understandable while we don't know how the damage calc is done or the priority of other Z-Moves. Still they seem to be very powerful, and a guaranteed KO even if it were only 40% of the time seems better than getting stat boosts on one of the weakest and unreliable Pokemon in the game. Which it's unreliability makes Eevee not even seem very good for passing stats due to other option being far safer albeit slower at setting up.

Finally, it's worth mentioning that Mienfoo and Timburr are two of the strongest Pokemon in LC. Chances are pretty slim that Eevee will be able to live a Fighting type Z-Move from either of them. Also, The only chance Eevee's Z-Move is banned from LC is if all Z-Moves are banned.