We are building a home and I'm thinking to make the home a little smart. This by adding WiFi light switches and maybe a couple of other sensors. Now I'm looking for a light switch that can be build in the wall (like a normal light switch) and that can also be operatate like a normal light switch. Does someone knows a light switch that can do that? Also it should be integrated in Home Assistant software.
The most obvious suggestion is to ensure that each switch location should have a neutral wire available. Either that, or you arrange the wiring to accommodate relay banks in an accessible location.
The question of smart and physical switches is complex, probably most restricted by safety concerns (that switch state should be persistent through a power outage, emergency services should have 'standard' access to light, etc.).
There are many smart lights which support both 'switch' and RF control. What is much less common is for the switch state to be exposed in real time to the 'smart' side (which would then allow scenes and sequences to be set up). The real restriction is that any 'smart' element needs to be powered 24/7, so either has to operate on leakage current or needs a neutral return. UK wiring at least does not typically provide neutral in the wall switches (just at the light fixture).
I'm using a sonoff-RF with a 'wallplate switch like RF sender' to retrofit this type of feature (where an original switch is now inaccessible), but that might not be the best choice for a new build. It might be a useful prototype though.
Due to the missing neutral challenge of retrofit, most vendors seem to be using smart bulbs or fixtures, and optionally short-range RF for switching. There is still a lot of evolution and churn, I think it is best to expect a mix of vendors (but the assistants do seem to manage to tie them all together fairly well).