Hybrid, in its basic release, would not work well as a multi-player game.
However, one of the Cry Havoc expansion issues contains rules for 3 and 4 player games. You would need that issue and additional miniatures (probably another 10-15) to do this.
Not necessarily true. I read the multiplayer rules in Cry Havoc #3 and the rules are as I guessed: you split into teams with players controlling their set of characters on each side. If so, the basic release would work well. There are 4 Griffin characters and 8 Scorpion. If you get a balanced scenario, you can play 4 player with 2 on each side.
Granted, the issue also has a 'free for all' multiplayer variant. This has 2 teams on each side and ALL are trying to complete the objectives and everyone is fair game.
You DON'T need additional miniatures for multiplayer UNLESS you want a massive free for all.