If by that you are asking if any American employee unions have branched into or spread to other countries, then the answer is yes.

There are many international unions that had their roots in the US and later branched into Canada, in particular.

Examples include the International Brotherhood of Electrical Workers, the Amalgamated Transit Union, the IATSE, the and International Longshoreman's Association, just to name a very few. The late 1800s and early 1900s saw the formation of dozens of American Unions, and many of them spread to Canada, or merged with smaller Canadian employee unions.

I will add one more to the list of unions; the United Mine Workers of America. I recently completed my theseis on radical unions In Nova Scotia and through out my research I found that many smaller populations such as in Canada lobbied after American Unions for membership. So im not sure if US unions really exported themselves, however, people really wanted to join them as they were established and much more powerful than local options.