No, it digivolves from the Tamer as-is.

No, it isn't considered a Digimon that would digivolve. When a Tamer would digivolve using this card's digivolution requirement, "when a Digimon would digivolve" effects don't trigger.

No, it isn't considered a Digimon that digivolves. When a Tamer digivolves using this card's digivolution requirement, "when a Digimon digivolves" effects don't trigger.

Such effects change the original color shown on the target card to the predetermined color shown in the effect. For example, if a Digimon's original color is red and it's chosen as the target for a "[On Play] [When Digivolving] Until the end of your opponent's turn, change the original color of 1 of your opponent's Digimon or Tamers to 1 non-white color" effect, then you choose a non-white color, and that Digimon's original color will become that color.

Its original color is changed, and it retains the gained color. Gained colors don't affect the original color.

The original color is changed to the most recent color.

The original color can be changed to any 1 color from among red, blue, yellow, green, black, or purple.

Yes, the digivolution requirements have to be met.