You can see from the bullet holes & pools of blood on some of the transfer figures that this set is as 'gory' as other Super Action Heroes sets in the same GK173 range (see links below).
We haven't yet seen any evidence of 'vanilla' version of this sheet; it's quite possible it was cleaned up, but on the other hand, preparing gravure rolls was very expensive & that would count against a revision.
However, there is a different transfer sheet from a later set in which some of the figures from this sheet appear, & where they are quite definitely cleaned up…
Four years after "Look Out Gotham!" appeared, Letraset produced a set with no title other than "Batman" (L64/A3 —&— L80/3), which combined artwork from both the "Super Action Heroes" Batman sets (the other set being "Batman: Gold Diggers of Gotham City").
This 1978 set was litho printed. Here is StellarX' "7 Wonders" version:
It wouldn't be surprising if when Letraset reprinted the two Batman SAH sheets as a single untitled "Batman" sheet, they made changes to the artwork. To print a new sheet for litho is simplicity itself, & the cost is negligible. But since reprinting a gravure sheet with even a minor alteration would have been expensive, until we actually see the "Look Out Gotham!" set with 'vanilla' artwork, we can't say for sure whether or not it ever existed.
If I were to make an educated guess, though, I'd say the sheet probably was cleaned-up & reprinted at the same time as the others in this run — early on. "In for a penny, in for a pound"!