My older tv is currently connected to Directv through the composite video cable connections. Would Roku work through a switchbox for the composite video cable connections?
Many do not work at all. Get yourself 2018 roku express, it has composite output, model 3910x. The newer 2019 express doesn't have the av output.
No current Roku offers analog video/audio outputs. The last one that did was the Roku Express+ (3910) that was released in 2017. Some users have been successful using an HDMI to analog converter, but others have had issues with them. The major issue is probably no current Roku supports a 4x3 screen. They are all expecting a 16x9 widescreen display.
Not certain why you mentioned a USB connection, but I've never seen any streaming device that was capable out sending video out a USB port. The occasional Roku that did have a USB port (such as the Ultra) can only use it for watching media from an external USB drive.
43 year old Large screen TV. Connected using Roku Express +, and HDMI2AV,. Connect coax cable to converter box and TV. Connect RC jacks of converter box to HDMI2AV. Plug in all electric cords and turn on TV.
Because the RC jacks do not work on this TV, I used a short length of coax cable to connect the converter box to the the HDM12AV. Then connected the Roku to the HDMI2AV.
I have an analog to digital converter box from the old days and decided to put it to use and cut down on cable. Works great with the HDMI2AV.
If your RC jacks are working, you won't need the HDMI2AV.