USB Power Hub PCB Design

I need a PCB design for a USB power + hub board to power a Radxa ROCK 5B+ and connect four 5G modems (Fibocom FM350-GL on M.2-to-USB adapters). The board should be ready for JLCPCB, with 2 prototypes.

Requirements

- 20V/5A USB-C PD input (standard USB-C PD charger, 100 W power bank) - 12V/4A USB-C output (fixed 12V, power only), only for the ROCK 5B+ and clearly marked on the silkscreen - USB 3.x hub with 4 USB-A ports, used for the 4 modems: each port supplies up to 2.5A at 5V at the same time (5G modems have current peaks), with its own current limit and power switch - 1 USB-C data-only uplink to the ROCK 5B+; the hub is self-powered and must not back-feed the host - If the total load is too high, the board should switch off USB-A ports one by one and keep the ROCK 5B+ powered - Input fuse, TVS diode, bulk capacitors Ideal Skills and Experience: - Expertise in PCB design and layout - Experience with USB-C, USB 3.x and USB power delivery - Familiarity with JLCPCB manufacturing requirements - Ability to provide schematics and layouts