Warning: The following contains SPOILERS for Batwoman season 3, episode 2, "Loose Tooth."
An episode of Batwoman season 3 suggested that the Aquaman of the Arrowverse may be a doppelganger of the DCEU Aquaman played by Jason Momoa. This would not be entirely unexpected, given that the DCEU has been confirmed to be a part of the same multiverse as Batwoman and the other Arrowverse series. The existence of doppelgangers of the same person living on different Earths has also been well documented throughout the Arrowverse.
While the Earth-Prime Aquaman has yet to appear on-camera in any Arrrowverse television series, his existence has been teased several times since Atlantis was confirmed as one of the many cities added to Earth-Prime following Crisis on Infinite Earths. Cisco Ramon made two trips to Atlantis during the second half of The Flash season 6, first while researching the new geography of Earth-Prime and then to get the parts needed to build a perpetual motion machine to fight Mirror Monarch. Despite this, the existence of Aquaman in the Arrowverse was not confirmed until a season 2 episode of Batwoman, where Luke Fox made a flippant remark about all the people Black Mask blamed for the death of his daughter, saying "I assume next week, it will be Aquaman."
The King of the Seven Seas was mentioned again in the opening scene of Batwoman season 3, episode 2, "Loose Tooth." Shot in the fashion of a horror movie, the scene showed a young college-age couple breaking into a private pool to go for a swim, only to wind up becoming a meal for the new Arrowverse Killer Croc. Just before Croc revealed himself, the male student disappeared into the dark water. His girlfriend presumed he was hiding under the water trying to surprise her, saying he may be able to hold his breath a long time but the world already had an Aquaman. She then added that Aquaman was "a lot more ripped," which seems a fair description of the Jason Momoa Aquaman, who was more muscular than most portraits of the character.
This is not the first time that an Arrowverse series had made reference to a superhero resembling someone else from elsewhere in the multiverse. After playing the part of Barry Allen's father, Dr. Henry Allen, in the first two seasons of The Flash, John Wesley Shipp also played the role of Jay Garrick, the Flash of Earth-3, who was established as a variant of Dr. Henry Allen. Shipp would later go on to recreate his classic role as the Barry Allen of the 1990 The Flash television series several times on The Flash and played a seemingly different version of Jay Garrick on Stargirl.
Given that, it is not impossible for there to be several versions of Aquaman who resemble the DCEU Arthur Curry elsewhere in the Arrowverse. Unfortunately, it's highly unlikely that Jason Momoa might make an appearance on Batwoman or any other Arrowverse series in the near future. While the affable actor might be agreeable to a cameo and has promoted various Arrowverse events on his social media in the past, Momoa is also incredibly busy with filming on the upcoming Aquaman 2.