There are unused copyright texts from previous Game & Watch Gallery games leftover in the game's memory.

Unusually for a Nintendo-published game, Game & Watch Gallery 4 was not released in Japan until its Wii U Virtual Console release in 2016, over a decade after its release in North America and Europe. However, there are hints that it was originally intended for a Japanese release in 2003, such as the presence of unused Japanese text within the game, a compile message in the Japanese version dated to December 24, 2002, and updated copyright information on the Japanese version's title screen.