Okay, I've been playing long enough not to ask this Q, but after you unlock a race ability (e.g. I switched to Mylarai and unlock enrich) when you change races again you will lose this ability correct (e.g. I can no long enrich after switch to a different race)?

Thanks!

correct.
you can only use the ability as that specific race

or profession, as per sab.

and as an extra:
for all racial/profession abilities, the timer is semi-shared. Specifically, the time of last action(of any ability use) is recorded and a new ability can only be used if it is at least the cooldown period after that.
So if you used tal to uplift a planet and switch to sab, you need to wait 8 hours before you use sab
if you used sab and switch to tal, you need to wait 40 hours before using tal
if you used sab, wait 8 hours(when you can sab again) and switch to tal, you still need to wait 32 hours.