In Singapore, how do I open up a WeChat pay or AliPay to use ePayments in China?

You can find a reliable platform to top up the RMB to your wechat account although you do not have a chinese bank account.

https://www.kavip.com/?-affi-75178 is best site

In Singapore u can only open up ur wechat wallet using any local bank credit/debit card,but to use wechat payment and top up,u gotta use a China Bank card normally.
Teach u 1 method without having to apply any types of china bank issue card.Download app:"KA-CN" from google store(app in chinese) to top up ur wechat wallet.It's a chinese app offer by Shenzhen IT company,accepts variety of payment mode,buy top up RMB currency paying in 5 different type which USD is the base one,cost abit more but worth it.After registering,thereafter all top ups purchase from Credit Purchase→Payment Made→Recieve $ In WeChat Wallet every transaction within 1 min +/- on average,ultra fast service,i highly recommend all travellers to China to use as backup(Unless if u're frequent long stayer in China or holidays in China alot then apply China Bank Card)👍👍👍👍👍👍👍
REMINDER TO ALL TRAVELLERS TO CHINA,MAKE SURE U DOWNLOAD ANY VPN(*BEST TO GET A CHINA MOBILE NOS.PREFER AS ALOT COUNTRIES OPERATOR NETWORK DON'T WORK OUT IN THE OPEN,NO PROBLEM WITHIN HOTEL WIFI)U PREFER IN UR RESPECTIVE COUNTRY & SUBSCRIBE BEFORE TRAVEL TO CHINA.PERSONALLY I'M USING "ExpressVPN",Happy Holidaying To All CHEERSSS🍻🍻🍻