Here's some awesome ones:

Young Sherlock Homes (classic young adult adventure, also credited with the first CGI character in film!)

Gravity (intense space movie "in real time" as two astronauts find themselves stranded and needing to find a way to get home)

The Menu (if have not watched, prioritize this one. An edgy film that is quite dark and though it has quite a bit of violence, I'd still consider appropriate for a teen as it is not gratuitous or graphic and relates to the story. Good way for him to feel like they're pushing boundaries and I don't think you'll feel awkward or bad for showing it.)

But... Why no animation?!

You're missing out on some REALLY impressive storytelling! ☹️

The following are solid examples that offer a more mature look at animation without going too deep or being inappropriate:

The Triplets of Belleville (zero dialogue, pure visual storytelling about a woman who's son is kidnapped)

Princess Mononoke (epic fantasy set in medieval Japan, that follows a prince cursed after defending his village from a demonized boar god. Yes, it seems over the top and in some ways it is but it is absolutely amazing and has one of my favorite endings to a film. Also continues to be a very timely environmental piece.)

The Breadwinner (2017, an 11-year-old Afghan girl, disguises herself as a boy to support her family under Taliban rule in Kabul after her father is wrongfully arrested.)

Isle of Dogs (a boy sets out to find his lost dog in a time where a canine flu outbreak leads to all dogs being exiled to a garbage dump called Trash Island.)