Both titles are official (source here), but we use the first official translation, which was "SpongeBob v nohaviciach", added by a Slovak mod and locked back in 2021. All other official titles should be added as alternative titles. If you want to change the title to "SpongeBob v šortkách", you must show us a proof that this title was used first.

Edit: According to the Slovak Wikipedia this series was first broadcast in Slovakia on Markíza starting on 2013-02-02. So I did some research and found the first Slovak mention of TV broadcast of this show in a TV guide from 2014-06-28, when Markíza broadcast it under the name "SpongeBob v šortkách". The first appearance of the title "SpongeBob v nohaviciach" I found in a TV guide from 2019-09-28, when it was broadcast in rerun by TV Joj.

So, my conclusion is that the first official Slovak title of this series is, as you pointed out, "SpongeBob v šortkách" from Markíza and that's why I changed it here. I added the title "SpongeBob v nohaviciach" from the rerun on TV Joj as an alternative.

I also changed your title of this thread a bit so that the change of the Slovak title of this series is easier to trace.