Not sure if the engine can support it and my guess is probably but, the relatively simplest but most depth-offering combat mechancs I've seen use raytracing for swings and are found in games like mount and blade, Mordhau, etc where you have 4 directions of attack (Left, right, overhead, stab) and a block with some games also having blocking in each direction and pretty much all of them giving a bonus for timing a block.
The dedicated block key being your sneak key causes it to fill your vision while trying to sneak, which is not ideal.
If it were possible, I'd first make it so you can block with any tool/weapon (even a stick) and give them some damage reduction values with the value being highest when you first block but reducing as you hold the block. Fiddle with the timing and now you have something like a shield which let's say blocks 3 damage flat. A buckler which blocks 5 damage when activated for .3 seconds then reduces over time to blocking 2 damage.
tadaa, you can now parry in combat, as long as attacks are properly animating a telegraph and the cooldown is working.
Some other things might be bleeding, burning, weapon oils (With the herbalism/brewing).
Maybe some weapons have a higher chance to cause bleeding which you need a bandage to stop, but will likewise cause animals to bleed out and maybe the monsters assuming they work that way. Likewise burning, just having ways to apply it. Lastly with herbalism/brewing maybe things like poison mushrooms can be used to actually coat a weapon in poison.