I saw someone use [name]Isla[/name] as a nickname for [name]Violet[/name] and I can’t decide if it works or not. I love both names (especially [name]Violet[/name] - my daughter’s name!) but I can’t tell if [name]Isla[/name] is too much of a stretch as a nickname. What do you think? Thanks for the feedback! 
I think it’s a very very big stretch. The only common sound is the I.
Big stretch, doesn’t work at all [name]IMO[/name]. If someone said, “My name is [name]Violet[/name] but I go by [name]Isla[/name],” I’d just assumed they changed their name altogether or were going by a middle. I pronounce [name]Violet[/name] Vy-let, (or sometimes Vy-uh-let), and [name]Isla[/name], Ees-la.
No. [name]Violet[/name] and [name]Isla[/name] are two completely separate, unrelated names. Why didn’t her parents just name her [name]Isla[/name]?
According to Nameberry, [name]Isla[/name] is pronounced eye-la not “Ees-la” as you said.
I can kind of see it, V-eye-let and Eye-la… but if I named my daughter [name]Violet[/name] I wouldn’t use [name]Isla[/name]. [name]Both[/name] are gorgeous names though!
I don’t think the Spanish or English pronunciation of [name]Isla[/name] is a good nn for [name]Violet[/name]- sorry!
If you call her by the French pronunciation of [name]Violet[/name] (which is more like Vee-oh-lay) then [name]Isla[/name] (pronounced Ee-lah) would work. Or you could do it Eye-lah as others have suggested.