[Suning]

Originally Posted by MysteryShadow

A young adult man is approached by a elementary school girl and soon after discovers she is the reincarnation of his deceased Mother.
https://mangadex.org/title/30333/sho...emo-ii-desu-ka Chapters 1-3 currently translated.
https://lhscan.net/manga-shougakusei...su-ka-raw.html Raw chapters 1-8 available.

I think reincarnation can count as age regression if the said person retains there previous life memories.

not really, i think reincarnation (with memories intact) counts as body transfer, not AR. Kyoukai no rinne had it too from rinne's mother and she retained her memories since she is a shinigami but i never counted it as an AR... (she is a 5 year kid but still treats rinne who is 15 year old as her son)
oh yeah there was also kurama youko reincarnated as Minamino Shuichi from yuyu hakusho but for me the only AR it had was from juri in the ura urashima vs kurama episode