function SourceMovie():void 
{
   var loader:Loader = new Loader();
   loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onLoadComplete);
   loader.load(new URLRequest('importedSwf.swf'));
}
function onLoadComplete(e:Event):void {
   var loaderInfo:LoaderInfo = e.target as LoaderInfo;
   addChild(e.target.content);
   var swf:Object = loaderInfo.content;
   swf.changeText();
}

SourceMovie();


// Runs function called changeText inside imported swf.
// To access variables, change "changeText()" to the variable name.

How to load an external swf.  Once its loaded, access it and use its functions and variables.

Load an external swf, use it and gain access to its functions and features.

ActionScript 3