As far as I can tell, yes. There are plans to connect the modern streetcar line to the southern loop of the McKinney Avenue line, and the parts of the loop that were built recently instead of 30 years ago (that is to say, about 75% of it) were built to modern standards to accommodate them. Plans haven't gotten far enough to consider the overhead wire arrangement, but it is possible to modify it to work with both. Alternatively, the modern streetcars are off-wire capable, and could simply run off battery, although the existing line includes a mile-long off-wire run along an old viaduct, and adding another mile might be much. I don't know what exactly their capabilities are.
Longer term regarding the whole line, there has been mention of the idea to one day convert the whole thing from heritage cars to modern cars, but nothing remotely concrete. Trolley poles will continue to be used for the foreseeable future.