Attacks » First Impression
If I move Wimpod to the Active position and then evolve it into Golisopod GX, would I get the bonus damage from "First Impression"?
No. Wimpod is not the same Pokemon as Golisopod GX.
Source: Burning Shadows FAQ (2017-07-20), TPCi Rules Team (2017-08-03)

Relevant cards

Note: All applicable cards may not be listed below.
SM3_129
SM3_148
SM3_17
SMA_SV48
SMA_SV48