In addition to republishing the content types from the hub, you will need to go into every subscriber (consuming) site collection -> content type publishing -> Refresh all content types. On this page you also have the option to view the error log - this will show you which content types could not be consumed and why. Usually it's because of a column name already existing in the site.
Also, the content type hub timer job and content type subscriber timer job(s) need to be run.... Which you don't have access to with SharePoint online (at least I don't think you do, I've only ever used on-premise). This means you may need to wait a day for your changes to take effect.