I would recommend fully physical. Flygon has a decent ATK stat but it isn't really anything special and certainly doesn't pull its weight on the special side with a pretty poor 80 base SATK. I can see Draco Meteor being somewhat viable however it isn't worth taking away investment from an already lackluster ATK stat especially when you consider it has powerful stab Earthquake and U-turn coming off its ATK stat. Outrage would be the better decision in this situation as it allows Flygon to finish the game off. Draco can only dispatch one Pokemon at a time due to the SATK drop.
Flygon @ Choice Scarf
EVs: 252 Atk / 4 SpD / 252 Spe
Defog is recommended by Smogon and can be used on a predicted forced switch (e.g. you coming on a LO Darmanitan. It won't be staying in)