All paid licenses is part of the Regular licence (read more below).
Free sprites are free to use, share and edit however you would like.
The Regular License grants you, the purchaser, an ongoing, non-exclusive, worldwide license to make use of the digital work (Item) you have selected.
You are licensed to use the Item to create one single End Product for yourself or for one project (a “single application”)
You can modify or manipulate the Item. You can combine the Item with other works and make a derivative work from it. The resulting works are subject to the terms of this license.
refer and involve 2dsprites.com.