What do Sunni Muslim recite after prayers during 9th and onwards of Zil Hijjah Month?
If you mean the takbir after the fard prayers then one can start with it after the fajr prayer of the day of 'arafah (9th dhil Hijja) end it ends with the sunset of the last day of tashreeq (13th dhil hijja) for a person not wearing ihram (doing hajj) for the one who wears ihram it beginns after dohr prayer of the day of 'id al adha (10th dhil hijja).
Scholars and fiqh schools have differences in this for example according to maliki sources takbir is done after 15 fard prayers (so they start takbir after dohr prayer of the day of 'id and end after fajr prayer of the last days of tashreeq according to ar-Rissala متن الرسالة from abu Zayd al-Qayrawani ابن أبي زيد القيرواني)! Some scholars say doing it in congregation is bida'h.
And Allah knows best!