YES!
I’ve inquired on the policy here with 0 response from Epic 
This inspired me to build a new type Online Asset Store that caters and supports Community-Driven Asset Modding.
There is a notion among many Content Providers that Game Devs only use Marketplace Player Assets such as Characters for prototyping. This is false. We want to use them in our commercial productions to save time and money.
If you’re a Game Dev like me, you desire your store-bought game assets to appear unique and to provide your Players customization options for Characters, Weapons, Vehicles, etc with store-bought assets. This is the challenge. Many of us purchase these types of Assets with intent to modify in some fashion to make them appear unique to our game. This is inefficient and negates the purchase in the first place. You’re back at square one, if you lack the talent to model/code etc.
Overall, This is money lost for content providers. Why not publish Assets such as Character, Weapons, Vehicles, Architecture that are readily customizable and supplement them with Asset Part Packs for further customization? A super savvy Content Provider would even provide an Embedded-able Entity Assembler like this one. If the content provider doesn’t have time to do this, then they provide license to the community to do it, and earn a % of the sales? That is what the TheGameDevStore.com is offering.
I’ve spoke about this issue over the past decade or more. I’ve suggest all sorts of ideas to get my point across. . It requires a paradigm shift in the approach to developing content for the marketplace, especially when taking in consideration of the Power UnrealEngine offers. The is lot of Content Creation power in UnrealEngine itself, in fact i would dare say that future version will integrate content creation equitable to 3rd party editors.