BUR #41069 is pending approval.
remove implication shiny_pokemon -> alternate_color
mass update shiny_pokemon alternate_color -alternate_shiny_pokemon -> -alternate_color
create implication shiny_pokemon -> official_alternate_color
I'd like to try this again because right now it's practically impossible for a regular user to search for non-official alternatively colored Pokémon, either in general (pokemon_(species) alternate_color -shiny_pokemon vs pokemon_(species) alternate_color) or for specific Pokémon (sylveon alternate_color -shiny_pokemon vs sylveon alternate_color)...
Woops, turns out alternate shiny pokemon exists for the search issue. The implication is still inaccurate to the definition of alternate color, though.
Updated