The Mobius uses Waves Nx with different defaults (Room Ambience set to 35 vs 17).
Windows Sonic gives true object-based audio in games that support it, and 7.1 channels in others. It can either downmix for headphones using a HRTF renderer like Dolby Atmos for Headphones / DTS Headphone:X, or output an Atmos bitstream over HDMI for an AVR. The API used by games is called Spatial Sound. It didn't work with MPC-BE because when using headphones the system mix format is still reported as 2-channel. MPC-BE has been updated to use the best supported format such as 7.1 channels instead of the mix format. In older sound card / virtual playback device based HRTF soflutions, the mix format is 7.1 channels. This works with older applications but it will never support object-based audio.
Given that Windows Sonic is the future for Xbox and PC games going forward, 7.1-channel HRTFs are not worth investing in. Just buy one of the Spatial Sound renderers from the Microsoft Store and use them with any headphones. You may have a better experience with DTS Headphone:X as it has profiles for many headphone models. Spatial Sound only works on surround streams and ignore stereo streams, so applications like stereo music players will not be affected. You can play music in the background while running a game, and the HRTF will apply only to the game stream.
You can set the DAC to whatever sample rates it exposes from the playback device settings. Spatial Sound only works at 16-bit / 24-bit 48 kHz.