I think it’s left intentionally ambiguous(or might vary depending on the series). They DO leave a lot of signs for Gwen being a supportive figure for transgender people. In Across the Spiderverse, she has a “Protect Trans Kids!” Poster in her room. Her dad has a trans flag patch on his uniform. Her superhero color palette is the trans flag. Pink, light blue, and white is always used when representing her.
Thats not even delving into how her story arc handles those themes/metaphors.
Looks like Ben Stiller to me