License for already downloaded/purchased megascans in 2025

Hello
I already ,purchased" all megascans on Quixel site and started downloading all on hard drive. I am learnig UE5 now and wanted to start making my own game in the beginning of next year. Can I use all megascans I already downloaded and launch game with all those megascans? What license are they?
Let’s say I would use 1000 assets like rocks, tress, etc. , would I need to purchase them in FAB or they are free to use for me up to some point where I would need to share profit?