Can you grow rooting plants without dirt.maybe in gravel with root tabs?

Certainly, but success and rate of growth will depend on the plant and the nutrient content of your water in the tank.

Yes

So if i use eady green with iton the plant will grow well without the plant using its roots for main foodeasy green and iron

I am with red repens java fern and crypt. All in like 1/8-1/4 gravel.

Yeah also you can find little pots submersible