Abra, the psi Pokémon from Kanto, can be found in the wild in Pokémon Go. Yes, Abra can be shiny in Pokémon Go!
If you already have a shiny Abra (or its evolutions), you may have participated in Abra Community Day in April 2020. The first few evolutions have only a slight difference when shiny, but Alakazam and its Mega form get more prominent pink accents, which rule.
What is the shiny rate for Abra in Pokémon Go?
As per old research by the now-defunct website The Silph Road (via Wayback Machine), the shiny rate for Pokémon on a regular day is approximately one in 500. Abra is not a confirmed Pokémon that gets a “permaboost” (meaning that it’s a rare spawn and thus gets a boosted shiny rate).
What can I do to attract more shiny Pokémon?
Not much, unfortunately. It appears to be random chance. Shiny Pokémon catch rates are set by developer Niantic, and they are typically only boosted during special events like Community Days or Safari Zones, or in Legendary Raids. There are no consumable items that boost shiny Pokémon rates.