I did try the battery/wired version, when wired it does not send the 433Mhz ping. AFAIK Only the wired 2k version, with the chime, uses 433Mhz…
I really like the US BestBuy special of Doorbell2k Wired, it has 32gb onboard and does constant recording… Alas not available in the UK and importing it is a PITA.
I have heard that eufy will allow constant recording soon, or at least rtsp support, but nothing yet…