You can use Amex to pay at Pump - Shell & Petronas.
You can buy Petronas fuel vouchers at Lazada and Shopee.
I bought Petronas RM50 fuel voucher at RM46 (plus 5% weekend CB for M2 AMEX / 8% online CB for Ikhwan Amex) last week. Today RM50. Should have offer on 7/7.
You may buy Petron fuel vouchers (valid for 7 days only, limited to stations in West Malaysia) RM10/30/50 at RM9/27/45, at Lazada this Sunday.
You can buy Shell RM30 vouchers at RM29.40, at Fave App.
You can use SPayLater (ShopeePay Later) on Monday-Sunday at Shell, Petron, BHP then use Amex to settle the SPayLater debt on Sat/Sun to get 5% weekend CB.
I don't pay to Maxis postpaid account, but at Maybank Islamic Ikhwan credit cards thread, some friends are using Amex to pay Maxis bills.
https://forum.lowyat.net/topic/4103568/+5320Search Topic, Keyword: Maxis
Normally I buy stuff from shopee by using maybank shopee credit card, as for lazada then UOB lazada credit card