If I have a Kecleon with the "Chromashift" Ability in play and two basic Water Energy and a basic Fighting Energy attached, and my opponent has a Jolteon with the "Thunderous Awakening" Ability and a Memory Capsule attached, would Kecleon still be considered a Fighting type Pokemon?
No, it would not. Thunderous Awakening would turn off Kecleon's Chromashift Ability completely, therefore Kecleon would be a Colorless type.
Source: TPCi Rules Team (2022-06-02)

Relevant cards

Note: All applicable cards may not be listed below.
SWSH6_122
SWSH6_122
SWSH4_47
SWSH4_47
SWSH4_155
SWSH4_155