You are correct; Facebook displays images in your timeline and in the News Feed at 470 px wide.
This makes having striking images even more important so that users associate the videos with your brand and are familiar with you when they do reach your page.
I read it works 2:3 ratio, but then opens full when selected.
I therefore used a 1080×1920 ratio, but when selected the top and bottom are cropped quite heavily.
So technically, you would want to upload slightly different image sizes for each.
Use tools like , through which you can create and program your tweets in order to save work time.