Hello, @Oliver Theiß,
1- I have checked your site on my personal mobile phone. There is no string word like you said it is working fine. you have a cache issue nothing else. Please check this video for a better reference: https://streamable.com/8rdui7
2- I am sorry but I am not able to understand what you want exactly. You are using the Loco translate plugin on your site and the word is already translated on your site. https://ibb.co/tPsM60b
Regards 8Themes Team.