If an effect changes under whose control a token would be created, that effect applies before Draconic Visitor's effect applies. If an effect changes under whose control a token would enter the battlefield, that effect applies after Draconic Visitor's effect is able to be applied.

If you create a nonartifact token that will be an artifact as it enters the battlefield, perhaps because of an effect such as that of Mycosynth Lattice, Draconic Visitor's effect doesn't apply to that token's creation. (This is because Draconic Visitor's effect modifies how the tokens are created, and Mycosynth Lattice's effect doesn't apply until you consider how the tokens are entering the battlefield.)

The tokens' characteristics are entirely replaced by 5/5 red Dragon creature tokens with flying. They don't have any abilities the tokens would have been created with. Anything else specified in the effect creating the tokens (such as tapped, attacking, "That token gains haste," or "Exile that token at end of combat") still applies.