Rosendo Alvarez is a bit of a forgotten fighter but he was a good one. His two fights with Finito Lopez and his quadrilogy with Beibis Mendoza were all close, hard fought bouts and he can be proud of his efforts. Ioka, however, has a slightly higher level of skill than Alvarez did. He is a tough guy with better boxing skills. Also, IMHO Ioka has been best at 115 pounds while 105 was Alvarez' best weight. Ioka is bigger and better but I think Alvarez is sturdy enough to go the distance. Ioka by UD.
Jinjinn, when you do post these fictional matchups, why don't you also post who you pick to win and why. It can give the conversation a starting point.