Can FileMaker connect to a Microsoft Access database?
e.g. connect to a Microsoft Access Database via ODBC:
MBS("SQL.Connect"; $Connection; "Driver={Microsoft Access Driver (*.mdb, *.accdb)};Dbq=C:\mydatabase.accdb;"; $name; $pass; "ODBC")
So pass to SQL.Connect a connection string including file Path and driver name. Optionally add user name and password as parameters. Be sure the installed Microsoft Access Driver has some 32 or 64 bit number as the FileMaker application.
Then use SQL.NewCommand and SQL.Execute functions to run SQL commands. Once you have some data queried from Access, you can easily have the plugin insert the data into a FileMaker table with SQL.InsertRecords or SQL.InsertOrUpdateRecords functions. Other way around you can do a SQL query in FileMaker with FM.SQL.Execute function and copy data with FM.SQL.InsertRecordsToSQL to the foreign database.