I think Jon would win but I just realised that we haven't really seen Jon in a serious one-on-one fight with someone superior or equal to him in strength yet. I wonder how he fights. Would Damian have given him any special training? I really want to know more about this.

Even though Yara might pick up a good fight with training and equipment she recieved, Jon's powers are superior. Son of Kal-El for the win.

Jon

Simple reason is he gets powered by the sun

Jon, I think.

His powers are greater, and Yara does not seem to have the training and battle experience to make up for his superior strength and long-ranging capabilities.

Nie, a Clark vs Diana is a different matter.

Clark would be diana

He gets powered by the sun which against amazons is like a instant win

No, no. Clark vs Diana isn't so straight forward. She is a demi-god now and she also has various blessings from gods and magical weapons, not to mention she also has at least a 500 year headstart on superman in terms of training and combat experience.

But yeah, in terms of pure strength, speed and resilience, superman wins easily.

Yara is the daughter of a god, I don't think we've seen her full potential yet.