Um WCS and WAR3Source are the same
War3sour is jsut coded in sourcemod

same shit though

u choose nightelf humanalliance orc shadowhunter etc etc
sameskills
evasion trueshotaura bash teleport etc etc

if anything it is better because more things cna happen in sourcemod than in ES variants such as teleport actually teleporting instead of pushing you threw the air like some weird superman,
Sourcemod WCS is the same mod but it has way better options.

You cant even compile your script if it has errors, it NEVER EVER crashes mine has been up 3 or 4 days already. If you have a problem compiling a race it tells you what line your error is on.
When u code something it already has awesome options for working with entitys or or saving global variables, or creating loops.

I am not putting down ES because I know it well and love it but as Iam learning SourcePawn it is way easier and coder friendly

but the main point is it is not something different than WCS at all it IS a sourcemod version of WCS.

but are still different in leveling strategies and race restrictions. War3Source involves more interaction between races, and has a buff/debuff system where races are expected to respect other race's buffs and debuffs.