At the moment, there isn't something specific within AFNI.
But the publicly available TORTOISE tool is probably the most comprehensive means for performing motion correction, eddy current distortion correction, and EPI distortion correction (for the latter part, it requires that you acquired data in 'AP-PA' or 'blip-up, blip-down' pairings):
[
science.nichd.nih.gov]
It usually requires a T2w contrast image as an anatomical reference, but when that hasn't been available for some past works, I have inverted the brightness of a T1w volume, and that seems to work well.
--pt