I assumed that, like Spider-Gwen, she's related to an alternate universe's Gwen Stacy - but she's actually Gwen Poole and she's apparently from an alternate reality where she knows all about the Marvel Universe's heroes and villains because she read about them in comics.
She wacky, a wild card with no powers who uses her knowledge and her unpredictable actions to surprise everyone.
I'm all for comedic characters, but when they kill people (as Gwenpool apparently has before), they stop being funny.
She doesn't really fit into this story at all, as the team visits a small town that's been hit by racist attacks, including the burning of a Mosque.
This would have been a fine chance to tackle an all-too-timely topic, but instead it's undermined by the addition of an erratic character.
Thankfully, she's apparently a one-issue guest. Hopefully we'll be back to focusing on the team next time around.