dont really agree to the comparisons drawn by moomin, whilst sophia is of greek descent etc, all the names quoted have been anglicised by years of use, whereas mateo is very much a spanish name not commonly used in the uk.
nothing wrong with that in itself just makes me think of those waiters you find in little pseudo french restaurants that lay on a thick accent and tell you they're called pierre. maybe im just a stickler for outdated social convention but similarly i feel like i cant call my son angus because im english.
if you actually like matthew but want to have something more different try and decide whats more important to you, liking a name that isnt spectacularly exciting, or having a unique name; thats not meant to sound negative i just cant phrase it well, everyones different (i love matthew fwiw!).