Hey Ken! I've done just this!
What I would suggest doing is creating a folder on the drive that you're moving called something like "FlightSim", and then moving your Official and Community folders into that.
Then, move the drive to the new PC, and reinstall MSFS. When it gets to the part where it launches the sim and wants to download the rest of the data, change the folder to point to D:\FlightSim (or wherever you copied Community and Official) and it will pick up the Official folder and it won't have to re-download all of that.
And your settings should be stored in the cloud, so those will transfer.
To be really safe, I'd actually rename Community to something like "Community.temp" before installing, and create an empty Community folder. Then, after you go through the install process, quit the sim, delete the empty Community folder, and rename the .temp file back to Community. That's just extra safety in case any of your add-ons might affect the install.
(Edited because I typed OneStore from memory, when in fact the root folder is "Official.")