As it has been said in the comments, you have a few ways to say that, but none of them are perfect (or it would be too easy):
Faire des économies de bouts de chandelle.
Is by far the most idiomatic expression with this meaning. As you noticed it is also not adjectival but you could just conjugates the verb and... tadaa!
Cette stratégie fait des économies de bouts de chandelle.
Note that this expression is highly tight to financial issues, or at least issues related to a measurable quantity. You can't say that someone "fait des économies de chandelle" because he is shortsighted.
At the opposite the word mesquin is closer to the general notion of being shortsighted and have a calculated generosity.
Other expressions (like "avare au son et large à la farine" or "économiser un sou et en prodiguer mille") seem to exist but are very rare. I have never seen those ones before today.