Different IMO. What Zelena’s done isn’t as drastic as what Regina did, she’s just sending them back to where they’d been before with a far less severe case of memory loss, so I’m doubtful that the same heart sacrifice was necessary to enact the reboot.
In fact I think it may have required the blood of the person Zelena hates most–Regina (hence the blood in the bottle)
Definitely a possibility, though I’m also wondering if maybe Regina’s blood was needed to reboot the Curse simply because she’s the one that cast it in the first place. Either way, I think that that bottle of blood potion is essentially taking the place of the bottle of true love potion from the original Curse, which will essentially put Regina in the position Emma was in with the first Curse, as being the one capable of breaking it, (which I think will happen when she kisses Henry after he gets his memories back).