I bought an Ergodox EZ a few years ago. While I enjoyed it at first, I realized that I was avoiding certain workflows because it lacked arrow and function keys, forcing you to rely on different layers.
I like split keyboards, and I also like thumb clusters, but I’d really prefer something with dedicated arrow and function keys.
Update for future googlers:
I ended up buying the Kinesis Freestyle 2 with the extra wrist rests. It’s not mechanical but I couldn’t justify the extra cost for both an ergonomic and mechanical keyboard.


I dunno if you’d consider it ergonomic but I use a Mistel MD770 and it meets your requirements. It’s essentially like a Keychron K2 cut in half.