Much of the technical talk is new to me so I apologize if this has been asked before. I am getting all the parts I need for my new gravel bike and I want to go with a 2x. I already have the GRX crank (48/31), cassette (11/34) and chain. My research indicates that the RD-RX810 is the ideal rear derailleur for this set up, but due to the the shortage of GRX parts, I am starting to look at the slightly used/new bike take-off option, I am chatting with a fellow about his RX812 that he has and could get it at an ok price. The Shimano website indicated the RX812 is meant for 1x.

Would this set up RX812 with my current 2x crank and cassette work without any issues or should I pass on the RX812 until I can find an RX810?