AMD has released an update revision of their memory support list for the Socket AM4 Ryzen platform. The past month or so memory compatibility and stability have greatly improved. Please do install the latest motherboard BIOS that holds AGESA 1006 firmware first though.
AGESA (v18.104.22.168) was largely focused on aiding the stability of overclocked DRAM (>DDR4-2667). AGESA (v22.214.171.124) also added 26 new parameters that can improve the compatibility and reliability of DRAM. There's a list available from AMD with all compatible memory. The list entails memory types from 2133 MHz up-to 3200 MHz.