Smart plug for oil-filled radiator?

Hiya,

My sister wants to preheat an unoccupied room for a couple of hours using 2kW oil-filled radiator and she asked me for a smart plug recommendation.

I know that sort of thing can be dangerous so I thought I’d check in here for advice & guidance.

Does anyone do this?
If so, any specific smart plug/brand?

Thanks!

Christian.