Pada akhir 2014, Zeng mendaftar ke Asosiasi Tenis Meja [[Singapura]] dengan harapan memperoleh kewarganegaraan Singapura dan bermain untuk tim nasional Singapura.<ref name=passport>{{cite web|url=https://www.straitstimes.com/sport/tablestta-tennisseeks-fengspore-tianweipassport-cutfor-from-national-set-up-as-stta-rejuvenates-squadzeng|title=Table tennis: FengSTTA Tianweiseeks cutSingapore frompassport nationalfor squad in shock move by STTAZeng|newspaper=[[The Straits Times]]|date=20162017-1003-2507|accessdate=2019-12-11|last=Chua Siang YeeChen|first=May}}</ref><ref name=passport>{{cite web|url=https://www.straitstimes.com/sport/sttatable-seekstennis-sporefeng-passporttianwei-forcut-zengfrom-national-set-up-as-stta-rejuvenates-squad|title=Table tennis: STTAFeng seeksTianwei Singaporecut passportfrom fornational Zengsquad in shock move by STTA|newspaper=[[The Straits Times]]|date=20172016-0310-0725|accessdate=2019-12-11|last=Chen|first=MayChua Siang Yee}}</ref> Ia memperoleh kewarganegaraan Singapura pada November 2019.<ref>{{cite web|url=https://results.ittf.link/index.php?option=com_fabrik&view=list&listid=113&Itemid=288|title=ITTF Eligibility Registration|website=[[International Table Tennis Federation|ITTF]]|accessdate=31 January 2020}}</ref>
