Nah… they would have to be US plates registered to THAT car, which I think would be difficult to get without transferring title, which most Secretaries of State probably require importation documentation (transferring from Oh Canada).  FL actually needs to inspect the car (confirm VIN) before they’ll issue a plate, with rare exception, as you know.
To the rest of your question, those Homeland Security border computers are piped into every state SoS, and a few other databases as well (e.g. security clearances, federal agents, etc.).  So the plate for your 500E “might” work on a debadged 300E of the same color, but that’s close enough to be intentional if they actually checked the VIN.  Check that, they have a separate camera on the VIN, which is likely cross referencing with the plate camera in seconds.  So, no, a plate switch won’t work.  But I presume you’re joking.
maw