I am almost certain it is watercress. We would not normally see it with flowers but it does have small white flowers. It is very healthy food.

it looks pretty, almost like butterflies

Is it growing in or near water?

It looks like a species of Cardamine to me though not one of the choice members of the section Dentaria with a creeping underground scaly rhizome, as you say, more like one of the weedier species from the genus with a rosette of leaves like a Bittercress.

Hi Fractal
It has fibrous root system,No water arrond where it grows.Likes cooler aspect.
The leaves have 7 leaflets (3 on eachside and one appical leaflet) The leaf is 2.5 cm long, emerge from the crown.
It could be a species of water cress which grows on cooler aspects .