With the 2004 release of ESB adding a line of dialogue to Palpatine and TLJ’s “Death Star tech,” the only film (in their current official presentations) NOT to invoke the Death Star in some way is The Phantom Menace. 😦
Uh…
D’oh! You got me; I hang my head in a moment of shame.
And TPM’s climax involves a Death Star-ish sort of explosion, but I’m referring to the ‘Death Star’ as such. So yes, I suppose Ep1 is the only one free of an appearance or name-drop. (In my fan edits, this could be said of 1, 2, and 8.)