I wish it will be available to connect EOS R5 and MOZA AirCross 2.
After installing the upgrade to the aie cross 2 gimbal, it is not possible to set the inception window manually.
I am not seeing the 750D on the list for the air cross 3.
For the Moza Air 2, the 750D can be controlled via a shutter cable but all of the controls you mentioned will not be accessible, unfortunately. The same can be said for the Air2S.
I believe it may be hard to find any gimbal that has these controls for your 750D, as far as Moza goes anyways.