Fellas, friend getting a smith to rebarrel an old 1892 and wondered if rebarrel might effect the guns COAL preferences. Levers can be fussy to loaded length, this one really likes short loaded cartridges. Would be convenient for his handloads after the rebarrel if it still did. Is it possible a rebarrel changes anything too critical?

Barrel has nothing to do with OAL. You can't make the barrel shank too long or the bolt won't close. What it is now, it will be then.
Affect.

dpcd has far more experience than me so probably I should be shutting up and listening instead of speaking my mind, but surely the ONLY thing that determines the ideal COAL from an accuracy perspective is the barrel?

From the perspective of feeding function, I agree that the barrel has no influence.

Having said all that, I would think that in the calibers the 1892 was chambered for (IE ones using relatively low sectional density bullets), and especially when using lead or copper-washed bullets, COAL should have little or no effect on accuracy?

He is omly concerned with its ability to feed rounds the same length. Thanks fellas.

Right; the design is specifically made for the 44-40, 38-40, 32-20, later 25-20, and later, renamed the 65 in 218 Bee.
Still, all those are the same length and you can't deviate much from that or they won't feed.
Modern 92s made in Brazil and Japan use 44 mag, 357s.