Not an expert on the character, but a quick search into the topic indicates that her originally being a Gwen Stacy variant could be argued either way. Apparently to take advantage of Spider-Gwen's popularity back in 2015, Marvel had a period where all their titles had alt-art covers with Gwen Stacy reimagined as other characters. One of them was a Deadpool comic, and it turned out to be rather popular with a number of cosplayers. As such one of the editors approached a writer and another editor about making a story around her, with the requirement that she be entirely unrelated to both Deadpool and Gwen Stacy, so that Marvel would be able to keep all the television and film rights, as opposed to Fox or Sony having them.
So based on that, arguments could be made that the original art of her that was a Deadpool cover was intended to be Gwen Stacy, while the counterargument would be that in any and all comics actually featuring her in the story, she had a backstory entirely unrelated to them.
Ultimately her real world origin boils down to "This quick cash grab of cover art combining two different popular characters was unexpectedly popular. Let's take advantage of that by making them an actual character, but make sure to not actually make her related to either of the characters involved so we don't have to share rights to her with other companies."