I found the problem here yourtheme/woocommerce/loop/result-count.php.
If I change the strings here directly in the file it works. About Loco Translate these strings are translated but are not considered. Is there any other solution than overwriting this directly in the template?
Thanks for the quick answer – but I suspect that this is rather a problem with reloaded Javascript files? If I do that with the find and replace plugin the whole string would be replaced every time.