[www.livescience.com]
The facts are simple. The grave of person suffering from a genetic condition that made them intersex, NOT non-binary which is a modern gender not a physical condition, was found in Finland. The person was buried dressed in female garb indicating she identified as female. Whether this was her choice, her family's or society 's we can never know.
She must have led a difficult life as ancient and medieval cultures were highly gendered and very binary. However she felt inside her cultural choices were Male/Female. As said she apparently went with female. She was well enough accepted to get an honorable burial with the usual grave goods for an elite female. The only odd note, other than her intersex condition, is the iron sickle across her throat. That is not standard, as far as I know, and could do with some explaining. The possibility that occurs to me is she was considered at risk of walking as a revenant and the iron tool was intended to prevent that.