Hmm... I just tried it in in Live Lite 10.1.7 with the AU version and it works here, I can see and hear playback of dragged tracks in both session and arrangement views.
Then again, I'm still running Mojave so maybe some Catalina users, or maybe even PG folks will chime in.

Sorry I couldn't be of more help.

- Jay
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MacPro 5,1/12 core@3.46GHz -- OS X 10.14.6 -- ATI 7970 -- 32 Gig RAM -- Crucial 500GB OS SSD -- Samsung EVO 1TB Audio/Sample SSD -- BIAB 2020 -- Logic Pro X -- Cubase Elements 10 -- Too many plugins