That's really disappointing if it proves accurate.
There was definitely a Man United level midfielder (starter or squad) in Hannibal - certainly at the levels of many of our midfielders of the last decade! And it really feels like he's never been given much of a genuine go at establishing himself with us. Very occasional starts, and a number of bit part sub appearances, but never felt like he had any legitimate run in the team to try and bed in and establish himself with us.
Hopefully, if he does go, he'll get that opportunity at Sevilla. I don't know what their midfield options are like, but I see they're struggling at the wrong end of the table so doesn't look like it might be as tough an XI to break into as in recent years.
Good luck to him if he leaves, but I'd be very happy to see him stay and get some genuine opportunities here.