This might've been brought up before, but towards the end of ROTS Yoda says that Obi-Wan that he'll be able to commune with Qui-Gon in his exile, and presumably learn the force ghost ability. I'm pretty sure "Qui-gon!" is even Ewan's last line in the trilogy.
Liam returned to voice the role as Qui-Gon's ghost in "Clone Wars" a few times, and most recently at the end of Rise of Skywalker. However it's worth noting that I'm pretty sure that the few glimpses we've had of Obi-Wan's exile in the Marvel comics and in Rebels Qui-Gon has not been present in any form (Unless you count Obi-Wan's journal entry about Yoda's adventure prior to TPM).
Given that decades have passed since TPM I'm not sure a physical effect will happen (Although Neeson hasn't aged too badly and of course there's always the Mandalorian effect they used on Hammil).
So should Liam Neeson return to do at least the voice of Qui-Gon?