Pokémon Go players are always looking for a sacred hundo version of their favorite Pokémon, the perfect IV choice that gives it the best stats for PvP or PvE. Even better is to discover a shiny hund, which gives him even more authority, because it is a shiny version of a particular Pokémon. Almost every Pokémon in the Pokémon series has a glossy version that gives players a small chance to meet it. For those who want to see if they can capture the shiny version of Mienfoo while participating in the battle league, you should not hold too high expectations.
The glossy version for Mienfoo will not be available when it is released on Pokémon Go. Like almost every Pokémon entering the game, Mienfoo will not get its shiny version for some time. We can expect it to be released sometime in early 2022, especially since it will be a Pokémon exclusive to the Battle League for a while. Fortunately, unlike Frillish, it will be much easier to obtain. You only need to reach the fifth position in the Battle League to get a guaranteed encounter, and then enter the general reward pool for Pokémon encounters.
Niantic usually does this for almost every new Pokémon it introduces in a mobile game. They will first release a new Pokémon, wait about a year, and then add a glossy version of it next to the event to increase its value again. There are a few small exceptions, such as Sylveon, who released his glossy form because of his first form, Eevee, which already has its glossy version available. Mienfoo does not have this luxury.