The Flash: Ralph Dibny Already Died Once In The Arrowverse
Before Hartley Sawyer made his debut on The Flash as Elongated Man, Ralph Dibny had a different story: he died, returning post-Flashpoint.
Before Elongated Man joined The Flash season 4, Ralph Dibny was dead originally in the Arrowverse. Ralph's history on the DC drama has been a shakey one since Hartley Sawyer was fired after The Flash season 6 when his old offensive and graphic tweets resurfaced. At that point, Ralph had been part of Team Flash since The Flash season 4 as the stretching hero is one of Barry's supporting characters in the comics. The Arrowverse version got far enough to also introduce Ralph's iconic love interest Sue Dearbon in the sixth season. However, after Sawyer's inappropriate tweets were discovered, they terminated his contract and The Flash season 7 has had to tackle his exit.
While Ralph may no longer be an active part of The Flash, his Arrowverse history was initially significantly different. In The Flash season 1, episode 7, "Power Outage," Eobard Thawne (disguised as Harrison Wells) confronts the villain Blackout. When Blackout accuses Harrison of not knowing the names of those who died when his particle accelerator blew up, he starts to list several people who lost their lives. Ralph was one of those who were killed the night it blew up. But this was in pre-Flashpoint as Barry reset the timeline in The Flash season 3.
Interestingly, Flashpoint undoing Ralph's death may have seemingly also rewritten his history in the Arrowverse. When Ralph first appears in The Flash season 4, they establish that he and Barry used to work together at CCPD. Their relationship was complicated because Barry got Ralph kicked off the force, which was eventually cleared up years later. However, when Ralph's name was brought up in "Power Outage," Barry Allen didn't react, meaning they didn't have that history pre-Flashpoint. Even if Barry has a grudge against Ralph, he would at least have felt something about hearing that he had passed away.
Ever since Sawyer's firing, The Flash season 7 phased Elongated Man out of the series. After Sue was framed for the murder of Eva McCulloch's husband, she went into hiding with Ralph. But when they returned, Ralph had been severely injured as his body was literally melting. But thanks to Team Flash, they got him into a healing suit as a clever way of not having to recast the role and write Ralph out of The Flash. If Ralph ever visually shows up on the show again, it will be interesting to see who takes over for Sawyer. But due to how many characters the show has already left behind, it wouldn't be shocking if Elongated Man is gone for a long time, if not forever.
With the way Ralph and Sue were written out, there are still ways for the latter to return to The Flash. Since they are traveling worldwide to take down Black Hole-like organizations, Sue could always come back to Central City without Ralph while he is on missions. Sue was always an excellent addition to The Flash and the show can still use her in other ways without Ralph. But in hindsight, it is interesting that if it hadn't been for Flashpoint, The Flash might have never brought Ralph Dibny into the Arrowverse at all.