In Pokemon GO, shiny Pheremosa has not been released yet. Players can obtain the Bug and Fighting-type Ultra Beast via Pheremosa raids by defeating it as a five-star raid boss. However, at the time of writing this, there is no way to obtain a shiny Pheremosa in Pokemon GO.
How To Catch Shiny Pheremosa In Pokemon GO
Like other five-star raid bosses, after defeating them, the defeated Pokemon will start appearing nearby and have a chance to be shiny. Once shiny Pheremosa is released in Pokemon GO, players will need to challenge and defeat this powerful Ultra Beast.
Once this has been completed, it will be possible to walk around and encounter shiny Pheremosa after spawning enough standard Pheremosa. Challenging and defeating multiple raids will also increase your shiny odds.
Make sure you are stocked up on Razz Berries and Ultra Balls for the encounter, as well, or you may fail to catch this Pokemon.
Players will need to wait until the next Pheremosa Raid event before they have a chance to encounter this Ultra Beast and, possibly, its shiny variant.