From googling it for a few minutes, it seems to be legit, but as it’s just a kind of marketplace to connect people, there seem to be complaints of a lot of bullshit like fake jobs being posted and stuff.
If she is serious about editing, it might be a possible first step to find some crappy jobs to help fill out a portfolio.
It sounds like it works really well. The physical size does sound quite large, but I’m not sure how that compares against other types of batteries.