The last comment about the responsibility might be a theoretical one as it might be more than tricky in case you have a damage to get even 1 cent from a company from overseas 
And indeed - most of the smart plugs are actually made out of non-burning material 
(which is very convenient because most fire insurances don’t pay in this cases at all because smo(u)ldering isn’t a fire - still the damage is often disastrous anyway). 
Device based on this design flaw 
were soled from various white labels (all produced by tuya) and had different maximum ratings including max. 10A and others max 16A. 
Like stated before you can just integrate your power usage over time directly on the plug an save it flash if you have control over your device. The moment your plug is online it can send the latest total energy to your HA server which will update your entity in that moment. As stated before HA doesn’t support synchronizing old timestamp/values. 
the ones coming preinstalled with esphom/tasmota are the easiest because they can be directly ota updated 