Using the following spec in a pokegive command results in the game crashing, generating this crash report: https://pastebin.com/EDHbti1p
Bulbasaur move1:vinewhip move2:tackle move3:growl move4:toxic
By testing out other combination of specs, I've narrowed it down to the move spec. Specifically, using one or multiple move specs with more than one word in them (like move1:vine_whip) doesn't work, and causes a crash on Singleplayer (haven't tested on multiplayer). When logging back in, the pokemon is created but without the move(s) with multiple words in them. It is more likely to crash when the move spec is combined with other specs that may have otherwise worked, or when there are multiple multi-word move specs. It does not matter which move the multi-word move is.