@Piru It's hard to talk with him, too smart probably :) the last answer was that we don't know what we talk about, and "The Wii doesn't have any little-endian video modes. I already told you DOSBox doesn't output 8-bit - that means when the video mode is 8-bit, DOSBox is sending 16 or 32-bit output to SDL (depending on default desktop depth)... If it were the wrong format, even 8-bit modes would look messed up."
But another user also confirms that he has _exactly_ the same issue on the latest up2date LinuxPPC: https://github.com/dreamer/dosbox-staging/issues/144#issuecomment-578533293
So it's already 3 oses have that issue: OS4, MOS, and Linux. So kind of naive to think that his Wii does things "right" and everyone else (includes far more popular Linux) do thigs wrong.
Sure it can be something else and not PCvsnoPC differences, but the bug is here surely. From his posts, it sounds like "it'd SDL, all SDLs around are wrong, and only Wii SDL do things right".