Watch List notes:

Phrygia, Aezanis. Agrippina II. Augusta, A.D. 50-59. AE 17 (16.6 mm, 2.98 g, 1 h). AΓPIΠΠINA ΣEBAΣTHN, diademed and draped bust right / AIZA-NITΩN, veiled bust of Persephone right, poppy and two grain ears before her; uncertain countermark behind. RPC 3103; BMC 93. VF. 

Howgego lists three countermarks for Agrippina II in Aezanis. While this countermark is uncertain, it does not seem to be one of the three listed.