Is there a word for someone who is a master of one particular weapon or martial art vs. someone who is skilled with many different weapons or martial art styles? (Maybe this can apply to skillsets in general.)
There's a common idiom for this: "jack of all trades, master of none".
However, that doesn't give you your two words, because if you said "Tom is a jack at martial arts" no one would have any idea what you meant.
Thus, as @Catija suggested I would use "generalist" for the "master of none". For the master level there are many terms available depending on just how good the person is, the formality of your situation, the flavor you want to convey, ...
Here is a semi-ordered, likely incomplete list: