On explaining weird applications of something in a scientific/technical context
The standard way to do this in formal language for papers is
novel
Interestingly new or unusual. ‘Four landers will explore for subsurface liquid water using a novel low-frequency sounding method.’
I would use the word unconventional. According to The Free Dictionary it means:
Not adhering to convention; out of the ordinary.
Not conforming to accepted rules or standards,
Consequently, your title would become:
On unconventional applications of "A".
You could try using the exact opposite of 'typical':
atypical
not typical : irregular, unusual
Alternative:
peculiar
Different to what is normal or expected; strange.
Particular; special.