Interesting paper by Arboretti (2021). Might be worth looking into to see how it can be incorporated. Need to determine if it is 1) worthwhile 2) doable from an implementation standpoint.
Arboretti, R., Pesarin, F. & Salmaso, L. A unified approach to permutation testing for equivalence. Stat Methods Appl 30, 1033–1052 (2021). https://doi.org/10.1007/s10260-020-00548-0