Please bear in mind that the following is from a "hack" photographer and not a pro.
The two telephoto lenses I use are a Canon 70-200 and a Tamron 150-600.
typically I use the Tamron 150-600 Telephoto at distance over the Canon and do not crop.
I have both a Canon 7D Mk2 and a Canon 5d Mk4.
In those above it was the 1.6 Crop sensor 7D Mk2 as it extends the range and I can get 10 FPS.
I was riding in the elevated bench seats mounted in the bed of a pick-up. Those were unsupported or I was braced against an arm rest or bed rail,and cherry-picked as there were numerous images that were not up to par.
I typically do not do post-photo processing as most of my pix are for myself, but did so in the pix above and below using "Raw Power" App.
Canon 5D MK 2, Tamron 150-600 f/5-6.3 Di VC USD lens, F/10, 1/800 sec , ISO 800, 500 MM.
Considering a 1.6 Crop factor that should be the equivalent of an 800 MM lens, if I understand correctly.
Best,
GWB