I tried googling it and kept getting articles on why X law is basically worse than the Jim Crow era. I learned that my Grandfather was arrested and possibly charged when he was deployed in Georgia and I'm hoping to find some information on his status out of curiosity.
The question is really about what happened to convictions. If you were convicted under, say, anti-miscegenation laws, are you still technically a felon? Or if you violated bus seating laws or whatever?
Let’s start with the easy one: there was no law about bus seating. One of the most important and insidious aspects of Jim Crow is that it was enforced by individual businesses under their "right to refuse service to anyone" -- the guise of "free association." White social pressure on businesses, not laws, created this part of the segregation system. Title II of the Civil Rights Act of 1964 took away businesses' right to refuse service based on membership in a protected class such as race or national origin. It did not vacate past convictions for trespassing.
Although interracial marriage was made a felony in some states, bans were more often enforced by charging people under different laws. For instance, after he married a white woman named Alma Toy, the famous boxer Jack Johnson was charged under the Mann Act, a federal law which outlaws “bringing” a woman across state lines for “immoral purposes.” A white Student Nonviolent Coordinating Committee activist in the South named Danny Lyon was also charged under the Mann Act, when his white female companion told Southerners she was married to a black man.
When a white woman announced to her parents that she wished to marry a black man, it was common for the parents to rush to a judge to deem her legally insane, so that they could forcibly imprison her in an asylum or in their home. Renee Christine Romano, in her book Race Mixing, gives five examples of this, all in the 1950s (pp.67-69). White men marrying black women were treated with much more respect, with parental rejection often limited to just verbal pushback. Neither response engendered a criminal record. In states where interracial marriage was illegal, it was common to simply annul the marriage rather than imprisoning the lovers (Phyl Newbeck, Virginia Hasn't Always Been for Lovers, p.55).
In general, Jim Crow rules were enforced with a light touch by the official legal system combined with violent intimidation from white society. I can't think of many specific felonies that the legal system would be obliged to vacate after the 1960s; this is the nature of both the way the system was built and the slow, non-restorative way it was dismantled. It is noteworthy, for instance, that Alabama did not formally legalize interracial marriage until 2000.
(I wanted to link to an AskHistorians book recommendation page on the civil rights movement for those who got curious about Jim Crow as a result of this question/answer, but I see that there isn't one. I invite interested parties to post a Meta thread if they'd like to help create one.)