OK, now I understand your point....IF you are willing to LOSE part of the frame, you can set shutter to higher than X-sync to control ambient light intensity, then use flash to properly illuninate the balance of the frame'.
...and can increase if needed the available flash guide number, on the contrary of HSS method.
This is the basic principle in presence of significant existing ambient light.
From there, everyone is free to embroider and bring his personal touch.
It is indeed possible in certain field situations to avoid any cropping in post-processing ;
and it is sometimes possible, provided there is no breeze, to consider images by assemblies in post-processing...