For this one its a disorienting effect reducing attack ability by half?  Single attacker couldn't us a bonus attack, a dual wielder would only be able to do attack/damage with one weapon?  How would this affect casters?  Would it cause them to take twice as long to cast it or just for that round?  Instantaneous casting would take the whole round instead of just the bonus attack time it looks like?  This spell also lasts for 1 minute so 10 rounds if I'm doing the math right?  Say a spell takes 2 rounds to cast (I'm not sure which one does, but say a homebrew does), would it take the caster 4 rounds automatically or do they roll each round to see if they can fight off the effect.  

Quote from Jynne >>

For this one its a disorienting effect reducing attack ability by half?  Single attacker couldn't us a bonus attack, a dual wielder would only be able to do attack/damage with one weapon?  How would this affect casters?  Would it cause them to take twice as long to cast it or just for that round?  Instantaneous casting would take the whole round instead of just the bonus attack time it looks like?  This spell also lasts for 1 minute so 10 rounds if I'm doing the math right?  Say a spell takes 2 rounds to cast (I'm not sure which one does, but say a homebrew does), would it take the caster 4 rounds automatically or do they roll each round to see if they can fight off the effect.  

Mostly, yes. This doesn't effect casters unless they have the Extra Attack feature. 

So looking at this, it just seems to be a worse Slow?

Slow does everything this does, in a slightly smaller range, gives more debuffs, and takes a lower spell slot. What is the actual benefit of using this instead of just using Slow?