Hello, Theo,
Thank you for getting in touch with us.
1/ “How can we change the cart button text?” – please provide a screenshot of the button and URL of page with it.
“Voeg toe aan winkelkar’ should be changed…”- so you already translated the text from English but can’t find where exactly did it?
2/ You need to contact support team of the multilingual plugin you are using.
We provide support for XStore theme only, and our theme is not the reason for mentioned problem.
We already helped you a few times with translation problems, but it is not our specialization, we hope for your understanding of this matter.
Kind Regards,
8theme team