Change of poop colour

Hi my LO is turning five months and fully formula fed. Her poo has always been dark green and pasty since birth. Frequency is about once every two days. Recently, it changed to a mustard yellow colour and smells much more stronger. She has been pooping at least twice everyday too which is more than the norm. Texture is slightly watery. Is this diarrhoea? She seems happy and doesn’t seem to be in pain when she is passing motion. Drinking well too. TIA!