Hello,
Sorry for the delay in answering. Please open up separate topics for different questions, to prevent a mess in this one.
About translation, go to Loco translate > Plugins > XStore Core plugin > edit translation, go to Loco translate > themes > XStore > edit translation of your language.
About image size of products, what exactly doesn’t work, describe the problem in more detail with screenshots.
Edit Footer using Elementor > settings of section > Advanced > XStore custom CSS code.
What about Xfilters? where and what did you read? describe your requests in more detail with screenshots, please.
Please note that we do not give a guaranty for full theme compatibility with all existing 3rd party plugins. Sometimes, not always, you need additionally customize the theme or plugin to make them work together.
Regards