Hi,
the best option (well, I am obviously a bit biased) is to use TmoleX. That is the native graphical user interface of and for Turbomole. It is usually part of Turbomole distributions and comes as an own installer for Windows, MacOS or Linux.
There you can either read in the whole job directly and then have the plt files ready to be visualized. Or, a bit less intuitive but more lightweight is to use COSMObuild as stand-alone tool. It is also integrated in TmoleX but can be started separately and independently too.
In COSMObuild you have to read in both the plt file and the coordinates to get the same visualization as in TmoleX.
TmoleX is also available in the free DEMO version from the 3DS site:
https://discover.3ds.com/free-download-biovia-turbomole-demo-version By the way: If you see plv instead of plt files - it is the very same format but can also contain vector fields. For scalar properties like densities it is identical to plt, so renaming plv to plt should work.