Rocky Marciano was terribly awkward with crouching and springing and angles, but devastatingly effective. The best true oddballs of efficiency right now might be Vitali and Vic (off the top of my head, at least), but awkwardness can be seen in so many fighters. Pacquiao's plethora of difficult angles can certainly see him considered as awkward, but I don't think that's exactly what you're going for.
Jones was awkward. Martinez is quite unorthodox. Pacquiao is also considered awkward and unconventional. Emmanuel Augustus knew how to throw opponents off frequently.
Mayweather: - He either runs around or used too - Or does his shoulder roll to take the punches on the shoulders - And just seems hard to hit (Yes Mosely hit him flush, but most of the time).
- Pernel Whittaker must have been awkward as hell for a opponent, especially when he chose against going 'toe-to-toe'. - Imagine fighters just extending their arms, and feeling nothing more than air and their elbow joints extending.