I have a list of them but I am too lazy to write down notes on each one justifying why they fall under the "Idiot Couple" category. Sometimes it could even be one of the side stories and not the main couple. But if you don't mind, you could try taking a look. http://www.mangago.me/home/mangalist/94526/
Alternatively, you might want to explore this list on Baka-Updates.
https://www.mangaupdates.com/series.html?category=idiot%2Bcouple&genre=Yaoi&perpage=50
Hope it helps.
Very eccentric uke,
http://www.mangago.me/read-manga/hatsuai/
Long term relationship, very funny how they try to spice things up!
http://www.mangago.me/read-manga/souteigai_love_serendipity/mf/c001/11/

can I get some recs of yaoi that have adorable idiot couples? i love those pairings the most