from reading, the HE-4xx or the HE-400i 2020 are decent for gaming.
the penultimate setup is the Beyerdynamic DT880 600ohm with a warm amp to tame the treble, that can be peaky. but these are open back dynamics, not planar.
edit - stroke of luck…check out the post by eng. he’s selling his 400i 2020 and the iFi Zen DAC:
I have the Zen DAC and it is awesome 