> I kinda don’t like PTP. Too complicated and requires specialized hardware.

At this stage, it's difficult to find an half-decent ethernet quality MAC that doesn't have PTP timestamping. It's not a particularly complicated protocol, either.

I needed to distribute PPS and 10MHz into a GNSS-denied environment, so last summer I designed a board to do this using 802.1AS gPTP with a uBlox LEA-M8T GNSS timing receiver, a 10MHz OCXO and an STM32F767 MCU. This took me about four weeks. Software is written in C, and the PTP implementation accounts for 1500 LOC.