The Grave Digger-op or not op

[Старый стрелок]

This weapon is good vs Almalexia, Gaenor, Vivec and Gedna? Magic Resistance must destroy this weapon, isn't it trash?

[Ghost]

It's a decent weapon. Regardless of it's enchantments working, it's still a Daedric dai-katana.

Resist Magic has no affect on Paralyze, though it can still be Absorbed or Reflected. While reflection can be a pain, generally anything that can absorb it won't last long enough to be a threat anyway. It's almost always useful.

Damage Health not only hurts, but permanently lowers the targets health, which makes their healing somewhat irrelevant.

[Старый стрелок]

If you increase his strength to 300-500, will he surpass Aevar the stone singer on average in damage?

[Ghost]

Assuming the enchantments work on whatever you're hitting, Gravedigger will do 110 on a hit, the mace will do 98. Gravedigger swings faster, so you'll be doing more damage, quicker, and the target likely won't be able to fight back.

Without the enchantments, the sword will do less damage per hit than the mace, but will still do damage faster, averaging more damage.

Increasing strength will increase both weapons damage by the same amount, so the question is somewhat redundant.