eWelink Single Fire Wire WIFI Module 2 Way support RF433Mhz No Neutral Wire Required,Alexa Google Home Voice Control 220V 240V|Home Automation Modules| - AliExpress
Sonoff mini Hack. No neutral? behind light switch No problem! No Live wire! #ElectronicsCreators - YouTube
Wall switch no neutral required
Smart Wifi Switch (no neutral wire required, eWeLink app, Burnett brand) | Shopee Malaysia
Sonoff TX single live wire Wifi switch - YouTube
Neutral vs No-Neutral Smart Switches - Homesmart Singapore