I have two offerings for you!

The Far Shore (godsoffortune) has a Marinette who would love to see Nathaniel around! The TDM will go up on the 1st of the month, and reserves will open that same day. The game itself sorts characters into two categories: gods and shinki. The former means they're filling in for a deity of your choice and the latter means that they've died and have been given a second chance in "heaven" as a spirit. This option includes memory loss and the ability to regain their memories of their former selves.

Melodies of Eternity (eternitymods) has a Marinette and a Pidge, so a Nathaniel or a Lance would be loved. The game itself is a FF-style game in which characters are able to pick up asterisks (Final Fantasy-style jobs) to master which grant them abilities. It's backtag friendly and the pace isn't terribly fast. Currently, the Red Lion is sitting with Yellow, Black and Green and the first three have their barriers up because their pilots are no longer in the world.

If neither of these turn out to be what you're looking for, I'm also open to PSL/musebox things, and I have more than just Marinette and Pidge to play with. Either way, I hope you find something you'll enjoy!