"Oh for cute" - grammatical interpretation?

So I'm from Minnesota, and while most of our English is fine, we're known for a few -- shall we call them -- adaptations. One of these is the phrase "oh for <insert adjective here>".

It's used as an exclamation if I have my terminology down (which I might not). For example, maybe I pull out my scarf (it's Minnesota, remember). My grandma thinks it's a cute scarf, so she says, "oh for cute!"

Obviously it's a compliment (in this case), and the meaning is clear enough, but I'm wondering if (1) it's grammatically correct, and (if not), if there's a way to stretch the English language to make it not quite correct maybe, but almost fit in.

I've lived in Minnesota for over 30 years. Here is my theory about "Oh for cute" (although I have scant evidence to back it up). Years ago, I often heard the phase "Oh for cute" with a pause between between the words "for" and "cute," as if the person were saying "Oh, for ... cute!" I believe the missing words are "... goodness sake, that's ...." The speaker at first intends to say "Oh, for goodness sake, that's cute!" But after getting the "Oh, for" out, they are overcome with emotion and cut straight to the adjective, "cute." Over time "Oh, for goodness sake that's cute!" morphed to "Oh, for ... cute!" and morphed again into "Oh for cute!"

Most universal equivalent I know is "Oh for sure" https://tenor.com/search/oh-for-sure-gifs

Used to be an affirmation but now a term that kids use sarcastically when talking https://www.urbandictionary.com/define.php?term=Oh%20for%20sure

Having lived in Minnesota now for 5 years, I can say definitively that the word "for" is used in place of the correct word, "how."

Using your example, "Oh, for cute!" ought to be grammatically said, "Oh, how cute!"

Another example would be "Oh, for fun." instead should be "Oh, how fun."

An educated guess:

"For" exists in both English and Norwegian - identical spelling and pronunciation, mostly. Obviously it's used as a preposition in English, but in Norwegian, it means "too" as in, "too much" or "too expensive". So, maybe this odd little habit of saying things like "for cute" or "for fun" is based on the original Norwegian "for" and not the English preposition "for"?