Nowadays, decentralized organization has become the emerging characteristic for AC-DC hybrid distribution systems (DS) facilitated by modern power electronic and information & communication techniques. This urges the DS to drop the centralized power supplying mode. In substitution, the DS is divided and operated as several self-adequacy subnetworks. In this paper, a two-stage Wasserstein distributionally robust optimization (WDRO) framework is proposed to provide a dynamic regionalization strategy for unbalanced AC-DC hybrid DSs.