Yes, you are right, the complete CH32X035 USB-PD adapter would be overkill, but I think it would be relatively easy to use the CH32X035 MCU (just the chip, e.g., in TSSOP20) in your own projects and PCB designs, since it already contains the PD PHY and provides a simple way to handle the protocol negotiations for PPS between your sink and the source (power supply). It is also quite cheap. You can look into the source code in the github repo and re-use some code. The toolchain is open and available for various operating systems. You do not need a separate programmer for the MCU, you can upload your firmware via USB. But, as mentioned earlier, I have not tried this myself, yet.