Are G7 and Gsus2 enharmonic equivalents
No. G7 are the notes G-B-D-F or degrees 1-3-5-b7 of the G-major scale.
Suspended means to replace the third, so Gsus2 is a Gmaj where the note B, the third, is replaced by the second degree, the note A.
Gmaj = G-B-D
As you can see, the 7th chord has four notes, major and suspended only three.
You could of course come up with e.g G7sus2 = G-A-D-F
Hope that helps!