yo "noobie" ronin.... you have that in game, but very rare, it"s a japanese medieval game man !!!!

1 - wakizachi (it's a short katana...but not all wakizachi...you need to found a "shield" one !)

2 - a weapon i've forget the name, like a "mini handed banner" (it's a war FAN or EVENTAIL de guerre) symbol of a general or daimyo...that can block as a shield too (Obunaga have one !) - maybe the name it's "TESSEN" or "GUNBAI"....or an other word !

3 - like shield in warband, you have HP stats for shields. you can see numbers like "500/500" under the name of weapon. in info at weaponsmith shop, or in the inventory (you need to check in lot of shop for found one ! maybe you can loot that after a battle too...or random event battle !)
4 - and finally, you have an "auto block" parameters in the game options
(good gamers can tell you "noobie"...but ive begin like this on the mod !)

good luck young ronin :)