I think it depends on how you would like to pronounce it (suh or say). I’m assuming that suh-leen is more common where you are, so adding the accent might help people remember that it’s pronounced say-leen.
There’s also the French fashion designer/brand Céline Vipiana who has a branch in the US, so say-leen might not be totally unfamiliar/confusing (?)
But it’s not pronounced say-leen in French either. It’s actually very close to the English pronunciation of Celine, just that the é is a bit longer than it would be in English. No -ay sound whatsoever.
You’d be right if only the [name_m]Mateo[/name_m] spelling were to be considered!
However, in Europe, Mateo/Matteo/Matheo isn’t seen as a very Italian/Spanish name, everyone uses it.
Coming back to this I think a big part, at least in the US is the unfortunate reality of racism and xenophobia. A white American person naming their child [name_u]Liam[/name_u] is at this point in time is not going to have a very different experience than an Irish person named [name_u]Liam[/name_u] in the US. However a white American naming their child [name_f]Parvati[/name_f] is going to have a different experience than a [name_f]Indian[/name_f] person named [name_f]Parvati[/name_f] in the US. For a white person it’s cool and unique while a person of [name_f]Indian[/name_f] heritage might experience being told their name is too foreign or hard to pronounce and will likely deal with racism and xenophobia due to prejudice against the culture their name comes from. Does that make sense? I do think there’s definitely room for nuance- for example let’s say a white child is adopted by an [name_f]Indian[/name_f] family and wants to name their child after their grandparents- that’s their family and culture. But that’s the rule of thumb I generally use.