The biggest issue that games such as this have when it comes to paying wages to moderators is a simple one...with many parts (read hurdles)
Moderator nationality....different countries have different wage/tax/other deduction laws to consider.....so if moderator A was paid the same as Moderator B before tax/deductions, chances are they would both come out with different amounts in hand due to their individual nationality and their country's individual earnings law
And believe me, that causes unholy amounts of paperwork and confuzzlement in the wages department
The best and easiest way, if moderators are to be paid up members of staff and taken notice of......and especially in a game such as this....have a set amount of gold placed into that moderator's account in a world server of his/her choice but making sure that it does not exceed any taxable limit for that moderator's country's earnings law.....for argument's sake and as a rough example a moderator could potentially have a base "earnings" of 20000 gold per week placed into whichever server they wish to have it
That would circumvent any taxation issues for that moderator's nationality
It can be done, it has been done before (when I was admin over 30+ vB discussion boards, the owner decided to not pay wages per se but give his moderation and admin team a little "thank you" each week for all the hard work done etc)