O Patinho Feio: A Combinação Perfeita (2015)

Both dramas are light and don't have a lot of revenge. As well as the main girl disguise her identity that she is wealthy.

Both plots of the movie and Perfect Match have similar plots by where the female lead has a skin condition.
Both have a school setting.
Both have female lead who is nice and a male who likes to tease the female.

Both female leads have self esteem issues and skin problems on their faces. Both male leads are handsome and fall for the FLs despite their appearances.

Both light hearted, enjoyable dramas with eye candy PUSH. Situated in a college background, childish yet intimate romance.

Both are cute series which are centred around a girl who fled to another place for different reasons, while hiding their identities of being wealthy. Plus, both girls were "ugly" in that place where they fled.

However, accidentally in love is in Mandarin but Ugly duckling is in Thai. (But then again, we use eng subs most of the time so... XD)

They're both very cute and romantic and the same actor stars in both dramas.