In the upcoming Zeta r23 update, non-replacer player voices can now be added to MGSV:TPP. They work much like outfits in that they’re applied when they meet the criteria: player type, parts type, camo type, head equip, etc. To demonstrate this, the MGSV mod “Naked ‘Big Boss’ Snake Voice Overhaul” by ToKillicide was ported to Zeta.
I will be looking at other player voice mods in hopes to port them to Zeta. Big thanks to ToKillicide for letting me port their mod!