How to beat Isshin sword Saint (no damage, sword only, no Kuro's charm, max NG+ and difficulty)

First phase: Parry/dodge/mikiri/jump. Similar to Fire Isshin phase 1 Second phase: For his non-running sword attacks, the rhythm is is 2 attacks-parry/dodge ahead-2attack twice-parry/dodge ahead. For spear and running sword attacks simply parry them all. Relocating can be important since the bot can glitch near walls/cliffs/boulders. Relocating can be tricky sometimes since he can use his gun while running to you. To avoid this, use his (jump back/dodge back+ spear attack) to relocate the fight. 1) When he uses the gun after this attack, dodge bullets by running sideways and relocate to your chosen location. Isshin will run to the location and do a simple attack which can be parried or dodge. 2) You can also use Mikiri on the spear thrust after gun attack to pull him towards you. 3) If you wish to keep pushing him behind, use dodge+forward during his (jump/dodge back +spear), to completely dodge his attack and get close to him for a free hit. This will also stop him from using the gun. Phase 3: Very easy. Most of the time, just use the 2 hits-parry-2 hits-parry rhythm. Dodge forward or sideways during his lightning to get a free hit. He will rarely use the jump back+ spear in this phase.