longer cables (~3m or 5m lengths) are more likely to have link reliability problems, e.g. host doesn't see DAC, audio dropouts, frequent disconnects/reconnects,
etc...
AFAIK, for Bifrost/Gungnir/Yggy using galvanically-isolated variant of Unison USB interface, the digital source always provides power to the Unison USB interface circuitry.
For Modius E, Modi+ (and Modi 3E predecessor to Modi+) you can get away with thinner DC power conductors in the USB cable by using the supplied AC adapter "wall wart" and matching short USB cable into the second port on the Modi+/Modius E.
If running longer lengths on Bifrost and Modi+, Modius E without wall-wart power supply attached to DAC's power port, look for USB 2.0 or 3.x rated cables with thicker (lower AWG or gauge) power conductors (e.g. 20 AWG is thicker than 22 AWG is thicker than 24 AWG etc.) Generally, USB cables with 20 AWG or thicker power conductors are difficult to find.
I have a 12ft (~4m) USB2.0 cable into Bifrost Multibit OG with Unison upgrade-- that cable is specified with "28 AWG/tp + 20 AWG/2C" where the 28AWG is the Twisted Pair USB signal lines, and 20 AWG wires are the two DC power conductors. Haven't tested a 22AWG version, but I suspect it should work OK. If not, best solution would be to re-arrange things so that a shorter USB cable can be used.