TRADOStag
To work with TradosTag (TTX) files in Trados Studio 2021 and later, first install the Trados Compatibility and Migration Power Pack. This adds the Upgrade Translation Memories option to the Translation Memories view > Home tab. Use this wizard to convert your TMs to the Trados Studio format (.SDLTM).
You can install the app from the Add-Ins tab > RWS AppStore or from a browser. For information on installing apps, see Install and manage AppStore plug-ins.