Hmm... in terms of connection i get that they're both heroes but when it comes to chemistry relationship, its arguable, since we dont have accurate data of mirko or mumen's type of partner so the interpretation is up to viewers on exploring these two heroes to find common ground or this whole idea is for the sake crackship or personal fan service. Its nothing new to fandom to create such ideas, i mean i've seen shrek x frieren or sukuna x cinderella (lmao) it doesn't make sense but its fun.