The only term I could find is right-left confusion, which makes immediate sense and is easier to remember than some Graeco-Latinate neologism. I also found a discussion (in the context of autism / aspergers) but only of the condition and solutions not terminology. I did find a whole slew of neurological disorders terms, though: e.g., anomia, agraphia, alexia, (I already knew of dyslexia and aphasia).

Ceci n'est pas un seing.