At what age can I start trying sleep sacks for my newborn instead of swaddling? I just can’t keep her arms in tight enough and she manages to get them up to her mouth which worries me that material will cover her mouth. Thanks!

Some babies do resist wrapping early & like to have their arms/hands free to touch their face or suck their fingers.
Sleeping bags (with arms out) can be used from birth. Ensure it fits appropriately so that baby’s head/face cannot become covered.

A safe baby sleeping bag is constructed in such a way that the baby cannot slip inside the bag and become completely covered.
The sleeping bag should be the correct size for the baby with a fitted neck, armholes (or sleeves) and no hood.
When using a sleeping bag, ensure that baby is dressed according to the room temperature.
https://rednose.org.au/article/what-is-a-safe-sleeping-bag

You could also modify her wrap by wrapping her underneath her arms
https://rednose.org.au/article/wrapping-babies