Nothing seems to be known about the artist Evi who contributed the supercovers for Progs 22 & 29.
There was an artist named Evi de Bono who appears to have been active in British humorous comics during the early 1980s, providing art for titles such as The Dandy and Topper. It's an unusual name of Maltese extraction, although de Bono was supposedly a Londoner[1], so it's possible that this is the Evi who also drew these covers. Unfortunately, very little seems to be known about this artist either.