You give very few details so it's hard to say really. No indication of age, size, dress style or budget if you're intending to buy new clothes etc.
I can't help with Disney as I have zero interest & late teen dc so well last that stage. Many years ago when we were on one trip to Paris we travelled to Disney for the day with dc. As I recall, the weather was very hot & I wore a summer dress & birkenstock sandals.
However, if I were going to Paris for 2 days now in may I would pack:
Travel:
Wide leg cos jeans
Ba&sh / veja collab trainers
Oatmeal merino draped jumper
Cream sezane t-shirt under so can peel off layers if warm
M&s buff colouredl rain coat
Day 1:
Straight leg mid wash jeans turned up
Navy round neck cashmere jumper
Navy silk shirt under
Raincoat
Day 2:
M&s ankle grazer black trousers from the collection range (these are brilliant!)
Cream ponte long sleeved top (me+em)
Trainers
Raincoat
I'd squeeze:
a lovely noa noa scarf
& a sezane chloe silk shirt in cream
suede birkensticks
into the bag in case i wanted to change for dinner in the evening or the weather was warner than I expected etc
Comfortable layers is usually how I plan trips like this
Hope you have a great time!