OK, but now "Arrow" fans are pushing to see Stephen Amell in a "Supergirl" suit.

That kind of "Freaky Friday" wish was just one reaction to The CW's intriguing new "Elseworlds" poster teasing this year's crossover event -- where "Destiny Will Be Rewritten."

You know the Arrowverse shows (or at least a few of them) have themed crossovers every year. This year, "The Flash," "Arrow," and "Supergirl" are holding a three-day event from December 9-11.

The "Elseworlds" special will feature a trip to Gotham City to team up with newcomer Batwoman (Ruby Rose). Superman (Tyler Hoechlin) and Lois Lane (Bitsie Tulloch) will also be there, along with Cassandra Jean Amell as Nora Fries, wife of Batman villain Mr. Freeze.

Stephen Amell and Grant Gustin normally play Oliver Queen/Arrow and Barry Allen/The Flash, but they showed their swapped roles when sharing the crossover poster on social media:

Fans had a lot of reactions to the Flash/Arrow switch -- confusion, excitement, pride that they guessed right, and some clever call-backs to past references:

 

Yeah, where is Supergirl in this whole mix? We'll find out pretty soon.

Here's when the big "Elseworlds" event happens on The CW:

• "The Flash" -- Sunday, Dec. 9, 2018 at 8 p.m. ET
• "Arrow" -- Monday, Dec. 10 at 8 p.m.
• "Supergirl" -- Tuesday, Dec. 11 at 8 p.m.

Want more stuff like this? Like us on Facebook.