Back to the OP, it appears that a portable solution (Android) is doable with RootlessJamesDSP.
I installed RootlessJamesDSP & Shizuku app (both available on Google Play store) on my HiBy M300 Android DAP. Enabling "USB debugging" and "Wireless debugging" in the developer options allow Shizuku service to register as a wireless device, 'intercepting' the Android audio stream for RootlessJamesDSP. Kinda of a hack, but it works, if somewhat finicky...
From Shanon GitHub repository, I downloaded the BRIR impulse response (wav file) and the HpCF GEQ correction (txt file... that's the trick!). I then open the HpCF file (Chrome for example) and copy the whole text response into the clipboard.
In RootlessJamesDSP, I imported the BRIR into the Convolver, and pasted the HpCF text into the Arbitrary Response Equalizer ("edit as a string" option) ........and voila !!!
Now, I am not completely sure whether the BRIRs work as intended: in my case, the M300 resamples system-wide to 192kHz. I thought that IR's were normalized, and independent of the sampling rate, but this comment from Shanon confuses me: BRIRs are provided as 2 channel WAV files with a sampling rate of 44100Hz. Does it matter?
EDIT: From what I could read, I don’t think it matters. The convolver output will be 44.1kHZ that may or may not be re-sampled by Android, but the result should be correct.
Disclaimer: the above process actuallly came from Joe Bloggs at HiBy: Joe has developed a room response and IEM correction for their own XOE IEM to be used with RootlessJamesDSP on the M300 DAP.
On a side note, I am also playing with Joe's DRX10K plugin, an interesting "zone range compressor/expander"-like. The plugin is available as an EEL2 script, so you can install it into the LiveProg section of RootlessJamesDSP, in addition to the above Convolver and Arbitrary Response Equalizer. It gives some dynamics fine-tuning options if you are not completely satisfied with your HP/IEM response. For example (per Joe Bloggs), if you have muddy bass, you can decrease the bass in EQ, and increase the bass dynamics in DRX10K. If you have sibilance, you can decrease the treble dynamic in DRX10K, and increase the treble in EQ, etc.