Is the old print of Recycle Energy from Neo:Genesis legal for tournament play since it has slightly different wording that the latest version from SM:Unified Minds?
No, the wording is different in that the old version works after Recycle Energy has reached the discard pile, but the new version works even before Recycle Energy reaches the discard pile. You must use the newer version of the card in tournament play.
Source: TPCi Rules Team (2019-08-01)

Relevant cards

Note: All applicable cards may not be listed below.
SM11_212
SM11_212
SM11_257
SM11_257