Hello so I would like iDisguise to be added! (Ahem, that isn't the full thing.)
First of all, iDisguise has Add-On plugins unlike LibsDisguises to make it better. (I'll mention those in seperate suggestions.)
Second of all, some players personally favorite iDisguise, not LibsDisguises.
In conclusion, iDisguise should be added!
EXTRA:
Version Range: 1.8.9, 1.9.4, 1.10.2, 1.11.2, 1.12.2, 1.13.2
Link: https://www.spigotmc.org/resources/idisguise.5509/