TL;DR: Of the 12 present or former Disney Princesses who "end up with" a man, 7 (most likely 8) of them are known to be younger than the man, and only Belle is known to not be younger.
Going through the official list of Disney Princesses, from the top:
- Snow White: Yes. As you stated, she's 14 (15 by the end of the story) and according to production notes, Prince Florian is intended to be 18.
- Cinderella: Unknown. She's 19, older than most Disney Princesses, but I can't find an age for Prince Charming.
- Aurora: Yes. She's 16, and while I can't find an age for Prince Philip either, he met Aurora shortly after her birth and was already a young boy by then, so he's a few years older than her.
- Ariel: Yes. She's 16, and according to the film's novelisation, Prince Eric is 18.
- Belle: No. She's 20 at youngest, and possibly older. The Beast is 20 for most of the film and turns 21 right at the end, when the last petal falls (it's fated to do so on his 21st birthday). So Belle is the same age as him, if not older.
- Jasmine: Yes. She's 15, and Aladdin is 18 - although he was initially planned to be as young as 13 before they aged him up.
- Pocahontas: Unknown. While she doesn't end up with John Smith, the direct-to-video sequel has her getting together with John Rolfe, as the real-life Pocahontas did. Pocahontas is 18-19 in the first film, but I don't know how much later the second film takes place or how old Rolfe is intended to be (for the record, the real-life John Rolfe was 28-29 when he married Pocahontas).
- Mulan: Most likely. Mulan is 16. I can't find an age for Shang but, given that he's already a captain in the army, he is probably older than that.
- Tiana: Unknown. She is apparently 19 (there's a sequel book about Naveen trying to find a 20th birthday present for her), but I can't find an age for Prince Naveen.
- Rapunzel: Yes. She turns 18 halfway through the film, her birthday being a significant plot point. Flynn Rider, meanwhile, is 26, the largest known age gap between a Disney Princess and her love interest.
- Merida: No. She doesn't fall in love with anyone.
- Moana: No. She doesn't fall in love with anyone.
- Raya: No. She doesn't fall in love with anyone.
For the sake of completion, let's also look at the two former Disney Princesses, plus two unofficial ones:
- Tinker Bell: No. She doesn't fall in love with anyone.
- Esmeralda: Yes. According to TV Tropes (obligatory time-sink warning!), she's in her 20s whereas Captain Phoebus is 31. (Quasimodo, funnily enough, is actually younger than her.)
- Anna: Yes. She's 18, and Kristoff is 21.
- Elsa: No. She doesn't fall in love with anyone.