1)Breastfeeding mother can eat on 9 ba Av?
2)If it’s permitted for breastfeeding mother to pump milk on shabbat, use wipes to clean baby (squeezing), sterilize feeding bottles using electric sterilizer?
1) Although the Gemara and the Shulchan Aruch (554) state that nursing mothers fast on Tisha Be’Av, If the baby is dependent on her milk and her fasting will cause a shortage or deterioration to the milk, a nursing mother is not required to fast. If the baby principle diet is other foods, or if the mother’s milk can be maintained throughout the fast, she does have to fast. It is important to drink plenty before the fast, and to stay in an air conditioned room etc. to avoid dehydration.
2) It is only permitted if the mother is in pain, and she needs to pump milk to relieve her pain; in this case the milk should not be pumped into a bottle but rather should be spilled.
For baby wipes please see here.
I’m not expert of how the sterilizer works, but if it goes on with a timer there doesn’t seem to be a problem. If there’s a specific melachah/issue involved please ask again.