Let´s say I have an Inspire 2, a Ronin and a Phantom -> means two additional remotes to the I2´, and two professional DJI Systems already.

Is there any chance to make the I2 cameragimbal working with the remote controllers of the Ronin or the Phantom?

That would be pretty neat!

No the controllers work differently somehow, that said the ronin controller is an older model that doesn't support the range capable nowadays nor the frequencies supported with the I2.

I'm sorry that RC of Ronin or Phantom even Inspire 1 is not compatible with Inspire 2 because of different transport protocol, please purchase its own RC on the safe side.