Of course you can remove them by making new image, but if have already an image and you don’t want to lose all the settings you configured just to remove plugins, there is an option to deactivate the plugins.
Below the reset option in the Settings/Reboot menu, you can remove and rearrange all plugins from your menu bar.
Please note that this does not mean that their contents are removed from the system, they are just removed from the overview above.
To remove specific contents, you need to do this in the plugin itself. If there is no autostart or running service configured in the plugin, deactivating it works without complications and does not impede your functionality in any way.