While not titled "Past Imperfect," this specific season and episode number features the crew meeting their own descendants from a divergent past.
Detectives Briscoe and Curtis investigate the murder of a former cover girl with hidden secrets. [S3E21] Past Imperfect
Xena has flashes of her past life with Borias while trying to protect a village from an army. While not titled "Past Imperfect," this specific season