Hello guys, I hope that I have chosen right category.
I have to pay a partner, I thought to make a withdrawal to him paypal (or others) account, I think that this is a good way, if not please tell me.
My question is: in this way, on the billing, the sender of the money is Themeforest or me?
Thanks 
Yes, this is a best way (you will not get additional comissions and save your money). Pay to your all partners from your withdrawal (add new for partner). You can have unlimited withdrawals even for the same methods (for example pay from swift to you, your partner and other partner).
Thank you dedalx, and Themeforest is sender of bill?
Themeforest will send your money, not you. What you mean about bill? You will get email about EVERY withdrawal part that this withdrawal was made (and how, what payment system), you can send this email to your partner to show that money is on the way.
Sorry dedalx, my mistake, I meant billing. Anyway you have solved my dubt, thank you very much