Spelloyal

More or less. The Great Sage prevented him from doing so, but at the same time he never cared much about it and never tried to recreate his sexual characteristics, being fine with his asexual body but always considering himself a man. The reason for this is probably the author of Tensura not wanting to write romance. In practice, Rimuru has the ability to change sex freely, as long as he has analyzed a member of the species of each sex.

The ring is only used to make portals. It is not necessary for any other magic. Wizards learn to use the ring first because it is easy and safe.

The surname is good, Lemu is a bit of a strange name, but you can get used to it. At least it's not a guy reincarnated in Japan with a Chinese name nor a guy reincarnated with an oriental name in a European fantasy setting.

The idea of ​​the fic is good, but the story started in what is basically season 4 or so, so many chapters are spent remembering everything that happened previously and there was a lot of really cool stuff, but unfortunately the fic started in the equivalent of season 4 as I mentioned.

Stella Redfield. This is probably a translated fic since the translator often gets characters' names wrong.

Absolute immunity to any type of physical damage, plus absurd lightning control would be worth it even with the weakness. Enel became absurdly powerful just by eating the Goro Goro no Mi and only lost because Luffy used the power of protagonism. In addition, the weakness only works in the world of One Piece since instead of being caused by the fruit, it is caused by the will of nature, with the greatest power of nature being the Ocean.

It's not a bad idea, but it's kind of annoying that the fic seems to start in the middle of the story instead of the beginning. I would have liked to see him developing his relationship with his sister, learning magic and developing his relationship with Asia.

This is a stolen fic, the original name is "It Started With Devils & Artefacts" by Dragon15681 and currently has 111 chapters here in the webnovel.