Oh, for the days when a girl could play with soldiers and prefer jeans and not have some fucking do-gooder chasing her around with oestrogen suppressants, because clearly she must be a boy.
My daughter prefers trousers because she can't get down the slide or play on a scooter in a bloody skirt. It's practical.
She likes Lego because it's FUN.
Not because she's clearly male and disordered.
Just let her play and dress however she wishes and get on with your day. Girls are allowed to like 'boy' things, because hey, they're not actually boy things. They're things. Your daughter likes things. This is not a medical issue and there's nothing 'wrong'.
What's wrong with 'looking pretty'? A hell of a lot, quite frankly, and you're going to be doing a lot more damage nagging her to 'look pretty' (therefore suggesting she's not currently pretty and needs to 'improve' herself for your approval) than you would if you just let children be children. I would never dream of telling my daughter to 'look pretty'.
She isn't 'completely different' to other girls. What, are they all in ballet tutus and ribbons and insisting on 'being pretty'? Utter nonsense.