I have a 2004 DOHC Accent hatchback. I have checked under the seat and next to the fuel pump. No filter, I was sold an inline-style filter so I don’t think it fits in the pump itself. Any ideas on where it could be I looked underneath the car following fuel lines and still didn’t find it.
If you have the 2004 Hyundai Accent then it is most likely part of the first generation according to Wikipedia:
https://en.wikipedia.org/wiki/Hyundai_Accent#Second_generation_(LC;_1999)
Apparently it is underneath the back seats – you can see a video of it being replaced in this video of a 2002 model (same generation as your 2004):
The video also covers the steps you need to take before hand to do a proper job of replacing the fuel filter.