Akuro (Alive: The Final Evolution) granted many humans special powers and accelerated regeneration upon coming to Earth.
Animal King: Lionelle (Akame Ga Kill!) grants its wearer powerful regeneration as its trump card.
The Hōgyoku (Bleach) granted Sōsuke Aizen a protective regeneration when he embedded it into his chest.
Yhwach (Bleach) granted his Sternritter various powers via his blood, some of which can have regenerative side-effects, such as Mask De Masculine, Gremmy Thoumeaux and Giselle Gewelle.
Nemu Kurotsuchi (Bleach) has a gland in her body that forces rapid cell regeneration at such a rate that if consumed, without the fail-safe implant, will cause the consumer to experience uncontrollable regeneration until the body self-destructs.
The Gekisen (Buso Renkin) grants its wielder, Genji Ikusabe, regeneration powers so long as he is holding onto it.
Haruto Kurosawa (Coppelion) dripping his super regenerative enriched blood onto Kanon Ozu, giving her increased regeneration rate.
Wood Golems (Disagaea) can bestow their regeneration abilities to others via Magichange.
Madara Uchiha (Naruto) granted himself regenerative powers from cultivating cells out of Hashirama's artificial body.
Yume Hasegawa (Pupa) fed her brother Utsutsu some of her flesh to transform him into a Pupa monster just like her, as Pupa monsters have accelerated regenerative powers.
Valerie's (Highschool DxD) Sephiroth Graal can use its power over life to give regeneration powers to others.