Is that grail ? If so, does time flow differently on Themyscira ? Because I highly doubt there was years between Robinson and GWW's run, in universe.
Also, I'm not sure if I like the idea of a reformed Grail. I know it's a big deal of Wonder Woman, managing to change her enemies into allies but... There isn't much great female villain left at DC, especially in the WW corner (Cheetah bores me to death for instance, I really find her extremely unappealing, as she is being portrayed). And I think that Grail, the dark reflection of Diana worked as an evil nemesis playing in the same category as she, with perhaps even more powers, thus being a an obstacle both physical and ideological to surmount for Wonder Woman.