I played this tank game once like 10 years ago however I never remembered its name. The game was 3d, had red and blue colored tanks, was third person, and had a plotline of the evil villian after their minions getting destroyed brainwashed/mindcontrolled your allies against you. The only other thing i remember about it was in one of the early levels there is a blue flamethrower tank ally that you can find in the level.
I would say it wasnt as i remembet there being a blue flamethrower tank which didnt require a powerup as it does in battletanx