I don’t understand wanting such a module.
You cannot use a straight-through or cross-over cable for such serial connections. You have to use a Roll-Over cable. So you’ll still end up stuck requiring a specialized cable… You’re better off just buying the USB-C to RJ45 console cables.
I guess you could create a special pin out at the RJ45 jack… but that just seems odd… Either way, you’re still stuck carrying cables.