Absolute Duo, Tate no Yuusha no Nariagari Recommendations
Both male MCs have the shield as a weapon, which make their way of fighting somewhat unique. They have a lot of females around them (harem). MCs want power to protect what they hold dear even if it means losing their humanity and becoming something even more.
The Rising of the Shield Hero is everything that Absolute Duo wished that it could be.
Shield Hero focuses on a charachter with a Shield overcoming trials and growing as a charachter over and over again, and Absolute Duo focuses on a main charachter with a Shield and attempting to overcome his enemies with his friends.
After that, the similarites differ.
The Shield Hero was despised in one series, but revered in the other
One is an Isekai and the other is an ecchi/school/harem anime.
If you enjoy seeing a charachter with a shield instead of a traditional battle weapon then you will like
-Both male protaganists use a shield for fighting and have a female to fight with a sword