When shooting photos black subjects w/flash would I still want to do -1EC ?

I'm doing portraits with a Godox flash and an umbrella. When shooting photos black subjects would I still want to do -1EC , or let the flash do the work?

The only real way to find out is to try it.

Remember black skin is actually a wide range of different colours and tones, and things like make up, skin oils etc can even effect how much light is reflected which impacts exposure.

Every portrait I do starts with a couple of exposure tests. I tell them I'm just checking the lights, but I'm really looking at the histogram to see where their skin tons are falling, and I adjust accordingly.