IYDK, Chelsea's been getting roasted online for dropping the comparison between herself to the actress while getting to know Jimmy Presnall on the latest season of "Love Is Blind." But she's now owning up to it big time ... saying she totally regrets making that comment and she's gone as far as reaching out to Megan Fox herself to apologize.

"I did reach out to her [Fox], and I was like, 'I'm so sorry I did this to you,'" Chelsea told "Entertainment Tonight" ... adding she's waiting to hear back from Megan.

Amid all the online heat, she did see some solidarity from Julia Fox. The model/actress, came through with some support ... commenting, "don't worry sis. I see it," under Chelsea's TikTok video where she begged anyone who'd ever said she looked like Megan to fess up.

Some other folks have also cut Chelsea some slack, saying they can kinda squint and see the resemblance ... but the overwhelming online vote says she's not a Megan doppelgänger by a long shot. Tough crowd!

You'll remember ... on the show, Chelsea spilled the beans on how people compared her to Megan 'cause of her dark hair and blue eyes ... and Jimmy was totally hyped by the name drop.

However, he realized he hadn't exactly hit the jackpot when they came face-to-face, admitting to the cameras ... "She definitely lied to me about some, uh, how she looked."