Sektor got his flight pose from Smoke, remember in MKD smoke had that finishing pose?

No he doesn't have invisibility powers

And finally, no chamelion is not a robot. Hes actually some sort of a reptile or lizard. And the reason he changes color is because he is a type of lizard called chamelion, most commonly found on the island of Madagascar, which have the ability to change color.

50% of the chamelion population is in Madagascar.

Questions answered, although just to mention that it's possible Chameleon is a Raptor to be specific, not a "chameleon" from present-day Earth.