I rember Gamaliel Diaz defeating Takahiro Ao in '12, then losing to him in 2018, is that the sort of thing you are loooking for?

What about Coutney Burton beating Emanuel Augustus in '04 by split decision (controversial), then getting knocked out by Augustus in 8 rounds in'06.

Derrick Gainer, getting stopped in 8 by Kevin Kelley, then defeating Kelley over 10 rounds in '98.