Let's try a rundown of the most relevant, outside what is obvious from the P&A section alone:
Master has a spell that automatically resurrects Fran once after it is cast. She also has 1 item that prevents her death once and another one that prevents it and then restores half her MP and AP.
Sword Lord Arts is the highest sword skill. Even lower versions grant the user so much fighting skill that it lets them fight opponents of vastly higher power (in verse stat wise, hence impossible to really quantify for our purposes).
Master's most noteworthy skill (aside from skill share's utility) is probably Skill Taker SP, with space-time & Dimensional magic in close second place. (Just read descriptions of those in the
"Skills" section on Master's profile)
Aside from that Fran's awakening makes her passively emit black lightning, which conducts through metal and just generally harms anyone that comes too close and doesn't dodge it. (It probably also has the lightning typical paralysis effect)
At the cost of mana Fran can, via Master's Physical Damage Nullification, negate all damage from physical (non-magical) attacks.
It should be said that Fran can and will, if the opponent lets go of his weapon, store it away in her dimensional storage, a pocket dimension in which time is stopped.
Aside from that she can create powerful barriers and for a drawn out battle Master's Mana Absorption Skill can be nice.
Lastly Urushi is nice, for numerical advantage and suprise attacks.