In order to configure Twitter Cards Tags for Magento 2 Blog Category Page please go to Content > Blog > Categories and click on the category you're most interested in to start configuring.
On the blog category page find the Twitter Cards Metadata section.
Twitter Cards Metadata
1. Set a Twitter Cards Title if you don't want Meta Title to be used instead. If it isn't set up the post title will be used.
2. In the Twitter Cards Description set the description of the twitter card. In case you haven't set it up the Meta description will be used. If none of the descriptions have been configured, the Default Description will be used.
3. Set the Twitter Cards Image, otherwise, Default Twitter Image will be used.
Once you've finished the configurations don't forget to press the Save Config button.