I'm not sure how to refer to this specific type of corner, that goes outwards. Searching for "corner wall mounts" returns results for "normal" corners that go inwards, as I'm sure you'd imagine.
I'm looking to get a 65" TV, for what it's worth. And I'm quite certain there are aluminum studs behind the drywall.
Yeah make sure you check first. I would probably find another spot because I'm not sure if any mount would actually be secure right there. Can you keep it on a stand or mount it somewhere else, because that might be a lot better.