The Eye-Able Assist tool is displayed in the language specified in the HTML attribute lang of the page. The language of the domain's texts is not taken into account.
To correct this, the language of your website should be set to the actual language of the page.
If you are unable to change the language, you can force any language in the dashboard under Eye-Able Assist > ‘Customise’ > ‘Advanced’ tab by adjusting the ‘Force language’ setting. You can change it from the default ‘Auto-Detect‘ setting to the desired language.
Note: This should only be a temporary solution until the langattribute is set correctly, as many external accessibility tools are based on the language set there.