The LC3T-14G370-BLL unit is MY20 F-Series.
The KS7T-14G370-BBH unit is MY19 Fusion/Focus.
These are compatible replacements as long as the KS7T-14G370-BBH unit is programmed properly. These are both NON-NAV, 8GB storage onboard. The NAV versions are 32GB. Since these units don’t have a lot of spare storage available, yes, they can get a bit sluggish at times. It seems like other than that, your functionality seems to be ok.
The following involves swapping out the Sync units in the truck, if you are up to it…
To be sure the KS7T-14G370-BBH is properly programmed, you can run the APIM Interrogator Tool, either from the Syn3 Updater or tutorial. In this case, run it from the tutorial to obtain the XML file. Run the file on each unit. Use the GB5T-14G386-AC file for both units. Once you have the XML files, you can post them here or PM.
Tutorial: APIM Interrogator Utility - Ford / Guides & Info - CyanLabs Official Community
Although the version numbers may match, the software may be different builds, 4" vs 8". This and the storage will be determined by the Interrogator Tool. Based on this information, it might be possible to modify the LC3T-14G370-BLL unit. (No guarantees here.)