Futsal is good to an extent. It is a different game. I do like it a lot. It is hard to just straight-out physical players.
There is no official-sized futsal court here. It would be cool if a place would build a couple. It actually could probably be done for not that much. They are a little bit bigger than a basketball court, and the flooring isn't that expensive compared to soccer turf, so you don't need the wall dynamic.
At a young age, you need to play soccer. Lots of it. They can do many things just by watching YouTube and Instagram videos and trying to make their moves. The massive amounts of videos out there is insane.
I have a young child who is roughly the same age as your daughter. For me, It has to be in this order for him.
1. Fun
2. Development
3. Competitive games
Fun affects development; development won't happen without competitive games. If you are getting trounced or constantly trouncing teams, those will help you. Development can occur through training and competitive games. You need to be put at the appropriate level, which is somewhat challenging but not disheartening.
If it isn't fun at their age, they will lose interest and want to do other things.
Not all kids are wired the same way through their competitiveness, interest, confidence, anxiety, etc. That doesn't mean it won't get there.