Can be controlled manually or via app (WLAN)

WLAN is a prerequisite for setting up and operating the device. It will not work without WLAN.

It needs WiFi to use all functions.
Only vacuuming can be started without WiFi in any room.

Yes it needs a wifi

I have asked Chat GPT, it said that Xiaomi Operates without wifi/ app as well. I dont have experience with manual operation