With pokemon bank closing, what are the rarest or most interesting pokemon that you can get from previous games?

Some examples include, Manaphy from ranger (especially a shiny), Quilava --> H-Typhlosion (maybe Ursaluna too?) from Colosseum, Mew from glitch in Yellow 3DS.

It's really interesting to think about what kind of pokemon will be considered really rare (like maybe pokemon with cool ribbons from older games which can be shown off in Scarlet/Violet.

Are there any other pokemon that can be considered cool collector ones?

Other random thoughts

-early gen Scyther, Girafarig, etc --> Hsiuan forms

-Espeed Dragonite or other gift mons (even if they lose moves)

-Ribbon masters

-Mattle Ho-oh