I started an online campaign last year with a general theme of the PCs (who serve a dragon kingdom) engaged as agents in a cold war vs a giant kingdom. I had plans for the war to go from cold to hot eventually.

However, work and life have made downtime prep very difficult and I'd happily transition to running something premade that could accomplish the same thematic goals.

I don't mind adapting from something that originally used neither dragons or giants, so long as the overall vibe is the same.

PCs are 6th level atm.

Any recommendations?

Tales from the Yawning Portal has an update of the old Against the Giants modules. I haven’t played it, but the original was a classic. 

That's definitely geared towards higher lvl but could make a great framework.  I hadn't considered theft, so thank you!