Senior Flutter Developer to create MXG Player

I am looking for someone to build a custom media player for the MXG format, the player will be expected to play stream based on a http multipart connection and also local files. The player will be embedded into a existing app. The successful candidate must have experience with either iOS ( Swift ), Android ( Kotlyn ) and should have experience wrapping native code with Flutter. Experience with the MXG format and using FFMPG would be greatly preferred.
If you think you are good fit to this job, please answer below question.
How much experience do you have with MXG and FFMPG?
I prefer to work with individual developers.