@SuperOniichan This isn't isekai at all, as far as we've seen so far. Reincarnation and isekai are certainly a pair very often, but there's isekai stories without any reincarnation and reincarnation/transmigration stories without any "other world" elements. This has presented itself as reincarnation only up to now.
As for the actual point of your comment, I'm not sure if you're asking whether this story specifically will have Maria paired up with a male romantic interest, or if that even happens in stories like this where the gender gets swapped somehow? If the former, no idea, but "he" does seem to consider himself entirely female in this life so it's not terribly unlikely. If it's about whether that happens or not in stories like this, then yes. Fairly common, possibly more common than the version of events where someone goes from male to female or female to male and then just keeps their old preferences entirely? Not really sure how that's split up in total, I've just seen more stories where getting gender bent does at least make people bi curious or such.