get a dumb hub (not a switch, switch's filter to each port via mac address ) and put it between your pc and the Internet router... the connect another pc on same hub running wireshark..(its free)....you can the sniff all the traffic on the wire/lan segment
I’ve only got the one comp- and I’m not quite that techy- you lost me right after ‘dumb hub’ (Had my wife not died at birth I would have been the ‘dumb hub’ lol