Same kind of mounting for sure.
However i an not sure if the following are the same.
"F" value
FOV ( Field OF View )
Lens back spacing / size of sensor it will work with without having vignetting in the corners, lenses are in general made to fit on a given sensor size,,,, or smaller will work too.
Regarding the case size i am not sure if there in the middle around GP 6-7-8 might have been a size and button placement harmony going on. the new GP10 is a bit larger than older GP cameras.
I think, if i was going side mounted camera filming into a prism filming while shooting, i would devise my own camera mount ( i assume that on such a devise there is a flat surface, or at least the tube the lens look down to work from )
I am going creative myself soon, have to make a unique intro video to the airgun channel i launch "soon" so my dji osmo action will soon be experiencing treatment i think no similar dji camera have ever experienced