The game boots and runs, but the audio is extremely distorted. The music is unbearable to listen to because of the distortion, and the game sounds often break up and stutter.
The mouse action is horrific. The mouse will disappear and reappear repeatedly throughout play. Pushing the mouse to the edge of the screen causes the mouse to lock up for a short time. Many actions with the mouse come with a long lag time, several seconds is typical.
Thus, the game is "playable" but it so unpleasant and difficult that I can't recommend anyone to do so. If you really want to play HoMM 2 on a Mac, go to https://dos.zone/heroes-of-might-and-magic-ii/ in a compatible browser and run it there. That version runs flawlessly.