(Beneath the case with the customer; this could help you as well, and therefore I blogpost it here.)
I have been talking to Ron Nieuwpoort from Amsterdam skateshop skatedokter.nl and he agrees that the left skate going outside edge could be both a skates issue (on the skate) or it has to do with posture. She had even problems in the grass which for me it is a slight sign it is about the skate.
However, it is just a sign! ;) More important is that she puts on her skates either at home on the carpet or in the garden or back on the grass next to he the skate track and then, using her female intuition (..) feeling and seeing if she stands up straight naturally.
Landing page of Skate•A•Round Amsterdam private workshops
Press on the Skate-A-Round logo for shortfacts about inline skating lessons in Amsterdam with a private inline skating teacher from Skate-A-Round. So we could make an appointment in a park in Amsterdam.
Have a nice skateful day,
Lex, skate teacher en personal trainer Amsterdam | Skate-A-Round on Facebook