Zigbee "status" device

Sometimes you’d like to check if a device (not smart, not connectable to Zigbee, Homey or whatever) is switched on or off, or if there is power connected to a system or device. Based on that status you can take certain actions. It can be compared to a doorsensor (door open/closed) or watersensor (wet/dry), but in this case it’s based on Voltage (230V or 110V if you like).
I could connect a smart light bulb and check its status (on/off), but maybe there is a smarter solution available.

PS. the situation is actually checking the on/off state of my tub heatpump to switch on/of the waterpump for it. Although it is a ‘smart’ heatpump and uses the Tuya app to switch on/off and set the temp, the Tuya connection to Homey does not work (although other systems that I have in the same Tuya account do work in Homey, this one doesn’t). The heatpump has a 230V outlet for the waterpump, but I also like/need to control the pump via Homey, not just via the heatpump.

Can you put a smart plug inbetween ? Then you can measure the power it uses, and thus see if it’s switched on or not…

I do have that setup (https://www.robbshop.nl/robb-smarrt-slimme-stekker-3680w-stroommeting-zigbee) and that worked fine for a while, but recently there seems to be a delay between the actual power used by the device (checked in Tuya) and the power usage shown in Homey. I have a flow that reacts to the power increase (by the heatpump powering up) with switching on the waterpump, but for a while now there is a delay in the value (minutes/hours) reported in Homey, so the pump is switched on too late (ie. heatpump turns off automatically with “low water flow”)