1st
If you’re not planning to use wired 3rd party speakers then the Port is the better (less expensive) choice.
2nd
I assume by LP you mean you want to connect a turntable. The turntable requires a pre-amp built in or external.
3rd
Using the Port you have to designate a Sonos (speaker/room) as the “auto play” room. Otherwise, you have to select a speaker/room each time you use the Port.
4th
As @Airgetlam suggested you can use a selectable switch to connect as many devices as the switch will allow. Selectable means you press a button to send audio to the Port from the device you want to use.
5th
The Port sends audio to the Sonos speaker of your choice over WiFi. If you want a more direct connection you might consider a stereo pair of Era 100’s and use a line-in port on either speaker connected with the Sonos proprietary line-in adapter from the switch.
6th
See a switch at the link below:
https://www.amazon.com/FlyroadUp-Bi-Directional-Stereo-Switcher-Selector/dp/B0CYHCGRXM/ref=mp_s_a_1_3?crid=3CIJTBW1WYSQD&dib=eyJ2IjoiMSJ9.YDPEtVjoBoU8wxoFqTc00Nue3SbmxwUL9B6oaqN9wQiTgw6igJrV-C5qrWP_obUWGvdvS5z-kqW6KaKVWLrT1cChhBBLS_uQWf3O9VQYMTQiJr-nVk6YbJWDDXKtQ1tXJoJ84Nqe8YqCIca9KXKhTK25h0AGGOn6IEPahkzy4yERyZyLapoa_gUIsE6NoJ8srTA-nB1WCC1suQOFle2njQ.oMdmKSqkzZxaR4m6V46dVJ0klg1g_rY8E7R5kKxSjrQ&dib_tag=se&keywords=rca+switch+box&qid=1762892679&sprefix=rca+switch%2Caps%2C321&sr=8-3
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