Hi Dario Giannozzi 

You need to download the 'Trados Compatibility and Migration Power Pack' because these functions have been taken out of the core product. 
Go to the integrated AppStore and download this add-on:

Once it is installed and you relaunch Studio, you will see this icon in your ribbon:

and this is where you will be able to upgrade your old TMs.
Walter

When I try to download the Trados Compatibility and Migration Power Pack, a page opens with the message, ""error":{
"code": "500", "message": "Could not find a part of the path 'C:\Inetpub\\OOS\_Apps\xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx\StudioPowerPack2022_17.0.1.37.zipper'."
}
}

Did you try to download from the integrated AppStore as shown in my screenshot?

And did you configure your AppStore as described here:
(+) Private AppStore - Wiki - RWS AppStore - RWS Community

Did you try to download from the integrated AppStore as shown in my screenshot?

And did you configure your AppStore as described here:
(+) Private AppStore - Wiki - RWS AppStore - RWS Community

I entered "power pack" in the box indicated by the red arrow. But the detra part of your screenshot does not appear. There is only the words "No plug-in available"

Check that you have configured the Private AppStore as described:  (Missing Wiki Page)