Dragon Quest 4 has one chapter where you rescue a fake princess, and later (in the same chapter) have to save another princess from having to marry someone evil. The twist? I mentioned that you have to rescue a fake princess, but in this chapter *you* are the real princess that she was pretending to be!
(It's too bad that, when viewed with a feminist perspective, Dragon Quest 5 regressed compared to its predecessor.)
SaGa Frontier has one part where you have the option to rescue a girl, but here, you are playing as a girl. In fact, there does appear to be a lesbian relationship here, and the girl who you might rescue plays a major role in the ending, regardless of which path you choose. (Also, that girl actually narrates the early part of this story.) If you want to see this particular story, choose Asellus as your main character.
(By the way, if you want a book recommendation, I would recommend Dealing With Dragons by Patricia Wrede; it's a wonderful story that makes fun of gender and fantasy stereotypes; for example, it starts with the princess running away to the dragon's lair, and not wanting to be rescued by a prince.)
Linko90: In general, I don't find 'rescue the princess' sexist, just an age-old tale that has been passed on from generation to generation.
The problem is that this trope has been over-used over the ages. (You know it's been over-used when it appears in an "excuse plot", like in the Mario series.)
Where are the games where you have to rescue a prince instead?