I picked up some drop kicks pretty cheap a week or so back. Until now I've been skiing Krypton Pros. When I initially tried on the drop kicks at home, they felt super tight, so I swapped in the liner from my Krypton pro. That liner, with a custom footbed in there too felt great in the full tilts! At the same time, as a test, I put the intuition from the drop kicks, into the Kryptons, and couldn't even get my foot in. The intuitions are super thick!
Then I swapped the liners back into their respective boots, and molded the intuitions myself (at work, in a ski shop), with toecaps and my footbed. My custom footbeds raise my foot up a bit, so at the moment, with them in, theres a lot of pressure on top of my foot. But my toes have space now (left foot felt pretty tight).
Skied in the drop kicks for the first time today, and not gonna lie they were pretty uncomfortable for a while, but after an hour or so they improved. This was just for a couple hours, so I didn't get a true feel for them, but they'll mold more if needs be, there's tons of foam there still. If it doesn't improve I'll swap the liner over from the kryptons, because I know that's currently more comfortable.
So, long story short, yes, you can swap liners over. No problem. As long as it's for the same boot size.