Hi, I noticed that the same place is standardized in different way

If I understand you correctly, "Sava, Taranto" is "Sava, Taranto, Puglia, Italy" from 1951 to today. It has had 5 different names over the years, one of which is "Sava, Lecce, Puglia, Italy" from 1882 to 1923. So the different names are already joined (unless there's another one elsewhere that I've not found).

As an experiment, I tried searching for historical records from "Sava, Taranto, Puglia, Italy" and it gave various answers including some from "Sava, Lecce, Puglia, Italy" but whether these results are because they've been linked as place-names or whether those 2 names just look very similar, I don't know.

https://www.familysearch.org/en/research/places/ is the URL to get to the standardised place list, which contains all the standardised places, each of which can have several different names over the years.

Am I missing what you want to do?