Yozakura-san Chi no Daisakusen

Both shows involve a weak protagonist, going through harsh training in order to fight within families involved with the criminal underworld in some way.  

Both series are about spy organizations with bodily superpowers while still feel grounded and realistic , not overly gritty, has plenty of combat Even if the premises are different  

Very similar in context. Family protecting the head and the MC working toward defending her from all threats. This is slightly towards action and less about romance. Pretty good. 

They both have a similar vibe so far. Both are rom-coms where the bride's family is full of colorful characters. 

In Mission: Yozakura Family, Taiyo joins the quirky Yozakura spy family, each member equipped with unique skills and distinct personalities, which gradually helps him overcome the trauma of losing a childhood friend in a spy-related incident. His loyalty to his wife, Mutsumi, and her family fuels his growth and commitment to becoming a capable spy. Similarly, in Malevolent Spirits: Mononogatari, Hyoma is sent to live with Botan and her Tsukumogami “family,” who challenge his hatred for Tsukumogami—a hatred rooted in his family’s tragic death at the hands of these spirits. Though his Saenome clan duties conflict with his growing bond with Botan’s Tsukumogami, Hyoma begins to heal and learn acceptance by seeing them as family rather than enemies. In both stories, the protagonists’ journeys are shaped by loyalty, love, and family support, allowing them to confront and ultimately transform their past traumas. read more 

For those who'll undoubtedly want something new to fill the void of MHA ending, Mission: Yozakura Family is another anime adaption from Weekly Jump staring a kind-hearted boy doing his best for others. Where Izuku had no quirk, got one, and uses it for good. Taiyo had no family, got one, and protects them with all his might. MYF is more comedy focused than MHA, but if you value character dynamics above all else then Yozakura is perfect for you. 

Both involve rom-com elements within the criminal underworld. 

Both Protagonists are orphans who, through different scenarios, join a loving spy family. Both have many comedic and wholesome moments.  

Both shows involve a weak protagonist going through harsh training and learning different martial arts techniques from a variety of strange masters.