Houtou Musuko to Koi no Ana
It's the, 'OH I thought you were a girl when we were younger and I had a crush on you then but we grew up and turns out you're a guy and I'm ~straight~ but oOP-' trope!
Why Are You So Kind To Everyone Except Me?
It started out with potential but I genuinely think the ml's love interest is a for real stalker and ML gets freaked out but simply ignores it and the story never comes back to it we're just supposed to be chill and pretend it didn't even happen. They actually could have made the story a lot more interesting (it was kinda of bland overall) by the long term friend turning into a stalker and dealing with that (I would want them to not end up together, and introduce second love interest, they fight etc etc it could have been really good)
Nigenaide, Rinjin-kun