Controlled residential ventilation - What should be considered when purchasing?

I have also decided on a controlled residential ventilation system in my house, which is yet to be built. Can anyone share experience regarding the following question:

Usually, the supply air is in the bedroom, and the exhaust air is in the adjoining bathroom. The bedroom is rather around 18 degrees, the bathroom around 23 degrees --> Is this even possible, or does the bedroom cool the bathroom or does the bedroom heat up? Can rooms even have temperature differences?

If you stand wet and naked in the bathroom: Is there then a draft to be felt? I have also read that some people have had a flap installed that temporarily blocks the exhaust air in the bathroom.

[*]What about your wastewater drain, for example in the bathroom? Or in the kitchen? That’s off-putting, isn’t it? No? Why not?
[*]What about the household garbage that stays in the kitchen for a few days?
[*]The toilet?
[*]Have you ever thought about legionella?
[*]Do you have a water tank anywhere, e.g. KVA or water filter?
[*]Entrance area: dirt from outside.
[*]Counterfeit money...
[*]What about the potting soil of your plants?
[*]Electrosmog I’ll leave aside... positive results surely only come from eating the food you heated in the microwave while it’s still warm.
[*]Yes, what can be so easily sucked in from outside? The exhaust fumes of your running engine? Or just the smell of horse manure nearby (a reason people move to the countryside), but that can really be annoying...

I don’t want to defend controlled residential ventilation, but still, a wake-up call regarding civilization

[*]Wastewater in bathroom and kitchen goes outside, away from me
[*]We only have a small household waste bin, which goes out to the trash at least every other day
[*]Toilet also goes outside
[*]Legionella? Sure, but the water is regularly heated for that
[*]Water filter: Yes, our fridge has a water dispenser/ice cube function. We never used it and therefore switched it off. So we don’t need this chlorine(?) filter either
[*]For dirt in the entrance area we use a standard vacuum cleaner
[*]...

I tinkered with my controlled residential ventilation system yesterday... and in case anyone is interested, this is what the fans look like after 3 years of continuous operation:



So I have no concerns at all regarding hygiene etc. with a controlled residential ventilation system