I have played both and still trying to finish odyssey. Both are differrent type if games. Origins was the step in the right direction that series needed and Odyssey further improves on it.
I prefer odyssey as its finally a proper rpg! And it works really well. The game is mire story driven. Combat requires skill. Hard mode is finally lives up to its name as u have loot to keep up with your gear.
Game is also massive. I am currently lvl 26 and 42 hours in on hard and i am only 26% in terms of storu completion!