The Blender Foundation is responsible for the popular, free, open-source 3D design software of the same name. The powerful tool has been a popular option for 3D development in video games but is capable of high-quality images and videos.
The Epic MegaGrant is a program initiative made to assist game developers, creators, and other professionals. The company has allocated $100 million toward various grants. Each award given is done so without any strings or stipulations attached. So Blender can do whatever they'd like with the money. Epic trusts that they'll use it well.
That said, it wouldn't be surprising if we saw an "export 3D model to Unreal Engine" option added to the engine as a courtesy.
Tim Sweeney, founder and CEO of Epic Games, had this to say about choosing Blender.
Open tools, libraries and platforms are critical to the future of the digital content ecosystem. Blender is an enduring resource within the artistic community, and we aim to ensure its advancement to the benefit of all creators.
Over the last year or so, Epic Games has received a heavy degree of negative criticism by consumers. This is mostly due to the creation of the Epic Games Store for PC and the influx of paid exclusivity deals Epic was making with developers. It's refreshing to see them do something like this without any expectation of profit.
If you're interested in 3D modeling or animation, we absolutely recommend looking into Blender and their collection of tutorials.