1. hardly disturbs, can also be deactivated by pressing on this cover or via the web interface. 2. yes, in addition to automatic, you can set 2G, 3G or 4G exclusively.

Hello Skilift, regarding your question, yes, it is possible to connect a printer via the network connector. For example, I have connected a printer and other devices for home automation. The range is better than with a Swisscom router, for example, and I have good reception quality throughout my house and garden.

I have no connections for external antenna on my E5180 - but reception is better than expected.

I then had a Netgear Nighthawk M1, simply operated without a battery on the power cable. But there are more powerful successors (M2, M5).

Theoretically, yes. In practice, every LTE connection has a delay. This has a disruptive effect on call quality. As an emergency phone it's ok, but for real phone calls it's rather cumbersome.

I read on the net that the lid of the Huawei also serves as a WPS button. Simply press it, provided WPS is activated on the router.

As far as I know, the unit does not have a built-in Voip adapter. So you would need an adapter or a telephone that is Voip-capable by itself. VoiP is sometimes problematic via mobile phones (the mobile phone provider must allow this, stability of the line, reception quality), so I would be rather cautious. It might make more sense to have a separate, inexpensive smartphone or a Fritzbox with LTE support and, of course, a suitable mobile phone provider.

Yes, that is possible. I have 8 devices permanently online and a data flow of about 1TB per month.

No, it is without battery. Port forwarding is not possible via 3G architecture (see also forums at Salt/Swisscom). It is a nano-sim.