Question

How early in the respective games can trades be done between X and Omega Ruby?

Answer 1

In XY, as soon as you catch a second Pokemon, you can trade.
In ORAS, you can only trade after Wally gives you the PlayNavfeature (obtained after he catches Ralts)

Source(s): Serebii, Personal knowledge
-Mega Luxray

Answer 2

You can trade in X as soon as you catch a second Pokemon.
In OR you can trade after Wally teaches you how to catch a Pokemon

Source(s): XY info, ORAS info