That’s fucking weird anon.
Essentially you have front focusing.
But to be sure, sacrifice a roll or two to test.
First of all, in the SLRs, does the viewfinder agree with the lens wrt focusing at infinity? I.e. when you focus using the lens infinity hard stop, is the viewfinder totally clear? And vice versa, when you focus through the viewfinder until it’s clear, does the lens stop at infinity?
Also is it really front focus?
I.e. is there a point closer that is actually much sharper than infinity, or is everything a bit blurry?
If you indeed have front focusing, something is wrong with the system. For SLRs the only way to get such an error, while the viewfinder shows clear focus, is either a misaligned mirror (resting closer to the lens than it should), or misaligned back (film sitting further from the plane it should).
Otherwise you should be getting exactly what you see through the viewfinder.
Rangefinders are a bit harder to diagnose, it could be a botched repair job that messed the shims of the lens/mount so it sits further away from the film plane, causing front focus and making it unable to reach infinity, regardless what the viewfinder patch or lens markings show.
But it’s really fucking weird to have that issue in three separate systems.
I guess make sure it’s front focus (and not some optical effect like less sharp at infinity (many lenses are like that, especially at wider apertures) or field curvature etc.).
And you can take it from there.
Bye how does the lens and mount on the Fuji look? Is it a bit banged up?
A less known fact is that fixed lens Fuji RFs are less fortified around the mount than the build of the rest of the camera would have you believe, and some bumps and accidental banging son the lens would force it out of alignment.