Hiya! I'm a goofy fella and have lately been wondering if we've discovered a way to save all the Pokemon trapped in everyone's Pokewalkers over the past many years, if not we should try and find one! Now that sounds like a silly thing to want but I disagree, to me this is what Pokemon is about!
Here's a list of all the info we have about the device
https://github.com/mamba2410/reverse-pokewalker
And here's a link to the gen 4 data structure, I'm unsure if this is helpful or not
https://m.bulbapedia.bulbagarden.net/wiki/Pokémon_data_structure_(Generation_IV)
Here are some test pokemon and saves from the pokewalker I got for research!
(Empty)pweep.rom
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(Karpy)pweep.rom
129 - Karpy - CD18759959C0.pk4
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(Arcesus)pweep.rom
493 - Arcesus - C64D915DC67F.pk4
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(Cool fish!)pweep.rom
349 - Cool fish! - CE4E99ABD544.pk4
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(Karpy2)pweep.rom
129 ★ - Karpy2 - CCE4861AFBBD.pk4
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If anyone can figure out how to rescue these trapped Pokemon I'd be an amazing breakthrough!
Thanks for reading!