If it's the Stand Slash you're talking about, I disagree only in that F-Atk is too slow a riposite move, and enemies will ALWAYS trade hits with this if they don't already outprioritize Arche. U-Atk is similarly situational, because against the things it's supposed to be used on (fliers) will also trade hits with it, and unless you dash it has no horizontal range.
With some enemies it's true that you can't use Wide Slash that effectively but some enemies get absolutely owned by it. Slimes in particular you can just spam Wide Slash over and over. If you don't have any other enemies bugging you and if you don't miss your timing you can have them pinned down the whole time. Those fox guys with the swords (can't remember their name) can also be pinned down that way but they're a bit more feisty so it's harder to get the chain started but once you do they can be pinned down. Once in awhile they break out of it but it's still pretty effective.
Edit: I forgot to add that Arche takes a step forward with Wide Slash so when you get to the point of encroaching on the Slime's sprite, switch to the U+Atk Arch Slash for one turn to push them back otherwise you'll start missing when you get too far inside their sprite. That's how you keep them pinned down.
Taking your time is also good advice. For example, I had some trouble with Mothbees at first until I just stopped... Literally. If you stand still they "stand" still as well and will just shoot stingers from a set distance. Duck, jump or block the stingers but otherwise remain stationary. Once they start flaying toward you dropping their sleep dust, smack them in the face with your sword. It cancels the dust and they fly back to stinger-shooting distance. If the situation is risky when they're flying toward you, just jump over them and try again next time. This tactic gets a little tricky when there are 3 of them but if you take your time it can be done with minimal risk.