Upload to Unity 3d asset store, legal question

Hey yall! I have been working on a user friendly "Audio volume menu". Which makes it easy for the user to seperate all their audiosources into diffrent layers, such as (SFX, Ambient, music and dialogue).

And my question is regarding the audio files, that I currently have in my project to demo my asset. All the audio files are downloaded from either https://freesound.org or https://www.bensound.com/ and I want to make sure if I can legally sell my asset with theese audio files included, ofc Im going to give them all the credits in the description at the asset store, but I want to be 100% sure if it is okey or not :s

https://www.youtube.com/watch?v=39FDm0lCa50