A few romcom anime that are mediocre subbed, but have hilarious dubs are Hajimete no Gal* and Kawaikereba Hentai demo Suki ni Natte Kuremasuka?* (better known as Hensuki). Both I watched subbed and was underwhelmed. Both I rewatched dubbed and laughed my ass off multiple times. You can tell the voice actors just had fun the whole time and it shows.
Three good short form anime romcoms I enjoyed were Tsurezure Children, Ojisan to Marshmallow (ecchi but between adults), and Okusama ga Seito Kaichou!*
Both seasons of Yahari Ore no Seishun Love Comedy wa Machigatteiru are great even though ironically I wouldn't classify it as a romcom exactly. It's usually more depressing than funny. Kokoro Connect is also good if you want a romcom that's also doubles as a depressing soap opera.
Kiznaiver tried to be Kokoro Connect and sucked. Don't watch it.
I recall thinking Jitsu wa Watashi wa was pretty decent.
His and Her Circumstances is a classic. So is Secret Girlfriend X. Both very well done, but also somewhat slow burns. Don't expect to love them from episode one, but stick with them and you'll be rewarded.
I dropped The World God Only Knows after 2 episodes. Big mistake. When I went back to it I actually really enjoyed it. Just gotta push through the first few episodes and the plot starts to come together. Also the way the show's dynamic flips in the 3rd and final season is unexpectedly clever.
I like Monster Musume no Iru Nichijou*. I don't care what anyone says. The monster girls are cute, the MC is relatable enough and the premise is silly. It's good fun.
The first 3 seasons of High School DxD* are the best kind of action romcom fun. The 4th sucks in my opinion, but some people liked it.
Full Metal Panic? Fumoffu is one of the funniest and most charming anime I've seen. Still my favorite season of Full Metal Panic by far and I wish they had just kept the series that way. You don't have to have watched any of the other seasons to watch it. It gets a heavy recommend from me.
Though very popular I didn't think Chuunibyou demo Koi ga Shitai! was anything special. Maybe you will.
Didn't know what to expect from Armed Girl's Machiavellism but it was actually very good. I recommend it. A fun action romcom.
Shomin Sample* is dumb, but it has a catchy opening and some legitimately funny parts. Plus the MC is a thigh man so he gets mad respect from me.
Trinity Seven is another fun action romcom with a MC who actually flirts with the girls and doesn't give a f**k. Of course nothing serious ever really happens between him and the girls, but it's nice to see a MC who's not afraid to "go with the flow" instead of swimming against the current, so to speak.
Seishun Buta Yarou wa Bunny Girl Senpai no Yume wo Minai is brilliant. The writing is very unique and the relationship between the MC and his girlfriend is much more realistic than most anime. Their conversations mainly consist of shitting on eachother, which is about as realistic as if gets. If you like it then also watch Denpa Onna to Seishun Otoko by the same creator. Good stuff.
That's all I can think of off the top of my head. Hope this helps.
Edit: I'll put an asterisk next to romcoms with ecchi (that I can recall) so you can personally avoid them, Parismio. Sorry I didn't see your next post earlier.