I like how this thread titled "Detailed Roy vs. Chrom Thread" features virtually no discussion of anything outside of recovering.
Anyway, it appears that Roy's jab has had its sweetspot angle adjusted to send more vertically, allowing for easier followups, whereas Chrom's has the angle Roy's sweetspot did in 4. Maybe. It's really hard to tell, but it definitely looks like Roy's sends more vertically than it used to, and I'm 90% sure Chrom's has a more horizontal angle than Roy's.
Edit: I'm pretty sure Roy's jab has a steeper angle now. In
this clip, Roy jabs a soccer ball, which as far as I know get launched at the angle of the attack that hit them, and it flies off at an angle that looks a lot steeper than 62. Why is it 62, anyway? That's always seemed a bit odd to me.
Also, there should be a Roy changelist thread.