Zaxxon and Super Zaxxon are definitely 8-way sticks and are not angle mounted (they couldn't really be anyway, as they are trigger sticks).
One of the best and easiest ways to check and see if a game is supposed to be 4-way or 8-way is to go into the game and see if it accepts diagonal movements or not. The ONLY game I am aware of that fails that test is Xybots, which came with factory 4-way sticks, but will accept diagonal movements if an 8-way is installed.