Displays the tag cloud dynamically from related articles belonging to the category of the display article
You are using a tag cloud of the standard, and you do not want to display tags that belong to the category not related to the article.
Try this widget.
Based on the category of the display article, this widget gets the tag from the article categories of related range.
For the article there is no category of post page, etc., or by setting
internal link article, it displays the tag by examining the related category.
If you check the 'internal link article', get a category from the internal links to articles.
Select Category related range
Other parameters : Display format, Sort by, Order, Font size, Number of tags to display, ...