I have been using VSCode for teaching the last few years, and routinely use a VSCode without plugins for that purpose, and Emacs keybindings work fine in its text area (the code editor itself). If it doesn’t work for you, then apparently something is broken on your computer. Not all keybindings work but the ones listed under Text Editing here certainly works for everyone else: https://support.apple.com/en-us/102650