Yes, steam could be considered an "emission", but that's clearly not how Fox News intends for its readers to understand this picture or its caption

Fox uses the photo above to illustrate today’s article on a suit to stop the EPA’s mandated conversion of trucks and farm vehicles to batteries: oooh, scary emissions! How awful!

The tone of the article itself is sympathetic to the plaintiffs, but the photograph is not, either through the ignorance of the editor and reporter, or malice — a combination of both is the safest way to bet these days.