I have never seen them newly hatched, but they are visible about a week old, they will be very tiny, like grains of sand and impossible to catch since they go right through the net
Some folks believe Anubias can be toxic to shrimp, especially when trimmed in the tank. I have anubias nana in my RCS and Malawa tank without any issues.
I've been doing some research on Malawa shrimp. They sound just like RCS! Main thing I couldn't find, is do they get to be the same size as RCS?