I have a different take. Once you must type out something like
exportPlot /@ Unevaluated[{myPlot2, myPlot3}]
then it seems to me like the OP should rethink the strategy from the start. That's because you could have just as easily done this:
altExport[name_String] := Export[FileNameJoin[{filePath, name <> ".pdf"}], Symbol[name]];
altExport /@ {"myPlot2", "myPlot3"}
The point being that in all of these cases, the OP knows both the sequence of characters that form the file name and the sequence of characters that form the symbol name. It so happens that it's the same sequence of characters, but that's immaterial, and I think the OP is actually letting it be a distraction. We must literally type out the sequence of characters twice regardless. In this scenario, we have two different semantic uses for a sequence of characters: a filename and a way to reference a Mathematica expression. I just don't see any way around that. Trying to force both usages through one bottleneck just isn't necessary. It's much, much easier to just preserve the sequence of characters you want as the filename rather than to extract it later through manipulating the sequence of evaluation. Again, we're forced to type out something twice regardless, so just type those things out in a way that's convenient for how you want to use them.
One way is through an association:
plots =
<|"myPlot1" -> Plot[Sin[x], {x, 0, 4 Pi}],
"myPlot2" -> Plot[Cos[x], {x, 0, 4 Pi}],
"myPlot3" -> Plot[Cos[x], {x, 0, 6 Pi}]|>
Another would be with DownValues:
plots["myPlot1"] = Plot[Sin[x], {x, 0, 4 Pi}];
plots["myPlot2"] = Plot[Cos[x], {x, 0, 4 Pi}];
plots["myPlot3"] = Plot[Cos[x], {x, 0, 6 Pi}];
With either of these strategies, we keep a clean semantic separation between the sequence of characters that forms the file name and whatever the Mathematica expression is that we want saved in the file.
Having said all of that, it's entirely possible that I've misunderstood the OP's real problem. After all, if it was just saving three plots, one could just as easily do it manually. That's why I assume it's worth spending some time re-thinking the overall strategy rather than shoe-horning in special-case handling.