The difference in block size wont matter since the VMDK files are staying the same.
The guest OS will remain mostly untouched, but it will ask you to configure the resources when you add the server again. Once the server comes back up it shouldn't give you any issues
Here is a list of steps modified from Spiceworks:
Connect with vSphere directly to the host it was running on, right-click the server and choose “Remove from >Inventory.”.
Browse the datastore it was on and single click the folder which has the vmdk's and vmx in.
Click on the "Download a file from this datastore to your local machine" and save it somewhere you will >remember.
Connect with vSphere directly to the host you want it to run on and browse the datastore of the disk/raid you >want it on.
Single click the root of the datastore and click "Upload files to this datastore" and select the previously >downloaded folder.
Once the file is uploaded go into the folder on the datastore and right click the VMX file and choose "Add to >Inventory".
Follow the on screen instructions. This will be asking you for Name of the server and resource pool.
When you turn on the VM you will see a message saying msg.uuid.altered, click on "I moved it".
Since it is a computer, anything can go wrong. Make sure you have a backup.