Can anyone advise how it might be possible to have more than one login page for different languages? Each version would contain different, localised, content for that country. Each country site will be hosted under a single site collection and using variations.
I think you are stuck to a single login page - but you can customize it based on the current context or locale.
You can use resource files for each of the locale's to customize what is displayed on the page based on the detected locale.
You can also display content based on the site being accessed - so you could say retrieve the logo for the currently accessed site, or perhaps a saved property that you've set on each of your site's, or content from a list.