I doubt it very much. If anything it could act more like an ND4, after all, a polerising filter is not actually meant to make the photo darker, but just get rid of reflections at certain angles. You can get PL ND filters though if you want to maintain the polarised look.
No problem. Another word of warning, polarizing filters are a little more tricky to master on a drone. You have to spin it round to change the polarization, like on a dslr, but you can't keep doing this as the thing is in the air! So obviously you have to set it before you take off. Problem here is you need to know you'll be flying in the same direction you set it up otherwise it'll look different!
Very frustrating as polarizing is one of the effects almost impossible to recreate post production.
I found its orientation by looking through it, then marked it, and fitted it to the lens, after the Mavic had started up, and the Gimbal had done its little dance.
Yep that'll do it! I'm going to try that! I normally put it in the drone and look through the camera on the phone when turning it. The only issue is if you point in a different direction you can get slightly different results, but this is normal not too bad. Also little tip, Polerizers work best facing 90deg away from the sun. So make sure you're flying perpendicular to the sun to get the best results.