"The model is really beautiful."
Translation:그 모델은 정말 아름다워요.
That would be "그 모델은 정말 아름다와요" in North Korea :)
According to the Northern standard, ㅂ-irregular words almost always retain vowel harmony. Therefore, when a verb/adjective stem ends with "압", ㅂ is replaced with "와". 아름다와, 가까와 etc. If a word ends with "업, ㅂ changes to "워", just like in the South. 무서워, 무거워 etc.
Rule regarding replacing ㅂ with ㅜ in adjective form is not affectred by this. 고마운, 아름다운, 무거운 etc. Not "고마온", "아름다온" or something like that.
As seen in the picture above (taken from a North Korean online dictionary), it is sometimes acceptable to inflect words the "Southern way" (아름다워 variant is mentioned next to 아름디와), but always the variant which follows vowel harmony is the default one. The only exception I can think of is 고맙다. While many Koreans from the North (and virtually every North Korean person in Southern dramas...) say 고마와요, it is more common to hear 고마워요 there.