Some themes allow you to set elements like footers via theme options. Once you translate the footer, you need to tell your theme which footer to display in each language.
To do this, go to WPML > String Translation and search for the ID of the default language footer. If you can't find it, click on the Translate texts in admin screens link and manually add it to the String Translation table. Then, add the secondary language ID as the translation. Your translated footer should now display on the front-end.
Some themes, like WPBingo, work together with page builders like Elementor and let you set footers or other elements like headers and templates via theme options or the WordPress Customizer.
For most footers and similar elements set via theme options, you need to tell your theme which footer to display in each language. This means that after translating the footer, you need to go to String Translation and search for the default language footer ID and add the secondary language footer ID as the translation.
