Welcome Conley, what is the weight and diameter? The texture of the coin gives me a bit of pause to even try to authenticate it. Welcome to CT.
I've never heard of Susan B. Anthany.. But the woman depicted on your coin is actually Susan B. Anthony
And the first pic looks like an ordinary copper-nickel clad coin that has spent some time in an acidic solution.
This one looks like it could be missing the clad layer. Very cool. Please take it out of the 2x2 flip and post new pictures. The other coin is damaged/altered
I think we need a pic of the 3rd side, a little bit of profile. The pics are deceiving. The other Susan is toned IMO. What are the weights?
I think they found a missing clad layer on the Obverse. It's possible on a SBA. It's clad. It has a copper tone not the brown toning color such as chemical or environmental exposure
Classic repoussé - https://www.coinworld.com/news/us-coins/repousse-and-encased-coins-part-of-exonumia.html (sorry, my spelling of terms derived from the French is poor. Frys - which I know are not actually French - and dressing (also not really French) is about the limit)
I don't have the right equipment to take a better photo, I wish It was a Susan B anthany it would be worth a lot, not to cool for my first post, the coins they are the same diameter, I don't have a scale. I can't figure out how anybody could alter the coin that much, they must have done it when they were making the coin.
Clad coins are much harder to press as a repouse coin, than a 90% silver half. Susan B's are for the most part spenders unless they are true errors and not altered. Try to get a weight on the golden toned Susan B, the second coin. That is the only way to tell if you have a missing clad layer.