Connected a ThinkBook using the plasma applet. A single configuration file does the trick:
thinkbook:~ # cat /etc/NetworkManager/system-connections/FRITZ\!Box\ Karl\ Mistelberger.nmconnection
[connection]
id=wlp5s0
permissions=
interface-name=wlp5s0
type=wifi
[ipv4]
method=auto
[ipv6]
method=auto
[wifi]
ssid=FRITZ!Box Karl Mistelberger
mode=infrastructure
[wifi-security]
key-mgmt=wpa-psk
auth-alg=open
psk=12345678901234567890
thinkbook:~ #
More at Wake-on-LAN, a working case - #4 by karlmistelberger