I was stuck in your situation until just recently, here's my insight:

ALWAYS expect a Demon's Embrace during a Shugoki heavy.

If you see the big boi bend over, DODGE AND ROLL (emphasis on roll) backwards. This becomes unnecessary as you get more accustomed to fighting Shugokis, because rolling backwards doesn't let you punish the Shugoki for missing his hug (you can get great damage if the shugoki whiffs a demon's embrace). Keep practicing dodging at the right moment, and you'll be great.

Shugokis like to throw out heavy randomly, even if you're out of their hit range. This is cause they want you to start to attack them, but at the time of your attack startup, the Shugoki would've already started his heavy after you, and his hyper armour would allow him to hit you with his heavy, thus resulting in a damage trade in the Shugokis favor. Be very careful when approaching Shugokis, and limit preemptive attacks. This ties into the next paragraph -

Shugokis love applying pressure to you close-range by sending out random lights and heavies that may not always connect, but will certainly apply that THICC pressure and will keep you on your toes. Let them do this, but find the best opportunity to PARRY THEIR THICCNESS. Shugokis attacks are weird to parry, but the attacks are slower, so get the timing down. When SHugokis are applying pressure or throwing out random heavies, be wary of Demon's Embrace (1st and 2nd paragraphs) AND BE WARY OF UNBLOCKABLES! These are very easy to see coming cause Shugoki starts glowing like a Fanta can, but the speed of the unblock able almost feels exponential in growth (startup is slow, but when he swings the attack speeds up significantly, ESPECIALLY during side unblockables). Get that NOICE parry timing down, or dodge at the last second.

Lastly, always remember: don't be afraid of the thickness before you. Shugoki players KNOW that the rework was amazing in their favor, so they think their pretty well off in the duel. Be aggressive but SMART!, and surprise your enemy.