Post in bulk based on category template

Let's start with an example of what I want to do. take a look at hardreset.info / devicesfaq.com

as you can see, the articles are almost the same, they only change few keywords / or based on title (device name)

let's say I have the same categories and a custom article for each one (hard reset, check imei, delete google account, etc).

Ok, now I want to post in bulk in all the categories I choose (check imei, hard reset, delete google account) at the same time without posting manually on each one.

If I am posting about Samsung A53, there will be posted articles like Hard Reset Samsung A53, Check Imei Samsung A53, and so on.

However, I am also looking for a way to get those articles from. I am thinking to have multiple single.php template pages for each category (hardreset.php, checkimei.php) and then include some code in single.php to show article if in category.

Can be done? Thanks a lot. later: still looking for some answers