Thank You Sathees for quick reply, using this can add mailto and get back the google list unsubscribe data instead of opening a https://doamin.com/unsubscribe page

We are exploring list-unsubscribe functionality. Does Adobe campaign Standard provide option for mailto in list unsubscribe. I have not found any documentation around this in ACS.  We have in ACC you add custom hearer and values, ow does this work in ACS.