ludo974 Hi
You can open the file: /templates/ja_landscape/html/mod_articles_category/isotope.php
Look for this code, approx line 146:
<a class="btn btn-primary category-link" href="<?php echo JRoute::_(ContentHelperRoute::getCategoryRoute($catid));?>">
<?php echo JText::_('TPL_VIEW_MORE'); ?>
</a>
at this moment, it will link to category page that you selected in module settings. You can change href param with your own link there.
<a class="btn btn-primary category-link" href="your_link_goes_here">
<?php echo JText::_('TPL_VIEW_MORE'); ?>
</a>
And override this language constant to translate the text: TPL_VIEW_MORE