The above is what Arbok looks like in R/S/E, the below is what Arbok looks like in FR/LG.
If I traded an Arbok from R/S/E to FR/LG, would it keep the R/S/E pattern, or would it change to the FR/LG pattern?
However, according to lore, if you were to take one Arbok from one region to another, it should keep it's patterns, but they didn't set up a system of different patterns on each sprite with a code to recognize which region it's from.
Hope I helped!