I have upgraded to Delphi 10.3.2 and Mac 10.15.
I added libmysqlclient.dylib to the project.
I get the following error:
Exception EFDException in module mysqltest2 at 000000010EAD1A0B.
[FireDAC][Phys][MySQL]-314. Cannot load vendor library [libmysqlclient.dylib, libmariadb or libmysqld.dylib]. Hint: check it is in the PATH or application EXE directories, and has x64 bitness.
The following sorted out the problem.
On the Mac I installed MySqlWorkbench
Right click on the application and show packages
rename the file to libmysqlclient.dylib
Add to the macOS64 Deployment settings
Set remote path to Contents\MACOS\
All working fine now.