Adapters might be the easiest solution for what you’re trying to accomplish. They make 90 degree angled usb c front panel adapters that would give you the right angle connection you’re looking for. None of the ones I saw on Amazon had a lot of reviews, so I’m not going to post a link. Just search “usb 3.2 header 90 degree” and use your best judgement.
Another option could be a USB 3.1 front panel to USB 3.0 20-pin header adapter… but again the highest rated one on Amazon only has 187 reviews. Use your best judgment unless someone else here can suggest a brand or say “hell no, they suck”.
there are ways to do this easily but it requires gimping the speeds of the port which makes the whole thing pointless as I have perfectly good and usable usb A ports also on the front panel.
The 90 degree adapter wont gimp your speeds unless it’s a low quality implementation. It’s nothing more than two connectors soldered on to a PCB.
Maybe someone will suggest of a high quality card that also has a rear connector. If not, I think you’ll be better off using a 90 degree adapter and a good card vs. a Shenzhen special.