Gary, check out the gPhoto doc - this is the library that most linux-based software will use to connect to cameras that have remote functionality:
http://www.gphoto.org/doc/remote/
I feel it's somewhat of a missed opportunity that Fujifilm reserve that capability for only the top-tier of their cameras - basically the "Pro" models, and the X-T3/X-T4, whereas pretty much any low-end Canon DSLR will work :/
I use an old X-A3 which has no remote capability, other than a plugged-in intervalometer which I use for longer exposures - all the recent models have a built-in intervalometer though, so they don't need an external.
Both the X-T3 and X-T4 use the IMX571 sensor - the X-T3 was the first camera on the market to use it. It is also used in other models, such as the X-T30 since.