Web Site Software is a fully customizable, content management system (CMS) with built-in SQLite database support. You only need a standard webserver with FTP support. you can execute SQLite command directly with Web Site Software.
Click on Menu
Tools, Options, SQL
Type SQLite Command
UPDATE entry_1 SET body = replace(body,'from','to');
entry_1 is table name, 1 means your first site, you should use entry_2 with your second site.
Click on “Execute” Button.