However I now own a physical Japanese copy and, as can be seen in the photos below, it loads with a Gameboy Color palette when played on my Gameboy Color or Gameboy Advance.
I apologise for the poor image quality, all I had available was an old Mobile Phone camera. I have provided the Gameboy Color photographs juxtaposed with the BGB Super Gameboy screenshots for comparison (it does look the same when played on a Real SGB as it does on BGB). (In my most recent test, I tried the Original, Rev A, and Rev B ROMs from Emuparadise. All played in 4-greys mode when set to Gameboy Color).
I would like to ask if anyone here knows anything about this.
The designation on the cart is 'DMG-APSJ-JPN' and the one on the PCB is 'DMG-LFDN-01'. If you would like any more information, please ask.
Comparison: (Photos scaled down)
Original Resolution Photos:
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