the pronunciation of letter i [duplicate]

In the word mentality, how should the letter i be pronounced?

In Longman, it's a shwa.

In Oxford, it's a shwa.

In Cambridge, its American dictionary(at the middle of this page) says it's a short I.

In Collins, it's a short I.

I'm confused by these dictionaries.

Is there a distinction between AmE and BrE? One say short I while the other say shwa?

Or they are both okay in the USA and the UK?

Yes there are some differences between American and British. One of the places you see this is in this exact pronunciation. But it doesn't matter for most people who speak English as a a second language, If you get to the point where you can 'pick' an accent, just pick either.

Even within the broad umbrella of American or British there is a lot of regional variation so you will hear any and all variations from native speakers.