When comparing Freesound vs Unity Asset Store, the Slant community recommends Unity Asset Store for most people. In the question“What are the best sources of royalty free game assets?” Unity Asset Store is ranked 2nd while Freesound is ranked 5th. The most important reason people chose Unity Asset Store is:
Those who have downloaded an asset can give it a rating (5-star system) and optionally a written review. Packages with at least four show their average rating, and total number of ratings. (Packages below the threshold show "Not enough ratings" instead.)
Ranked in these QuestionsQuestion Ranking
Pros
Pro Creative Commons licensing
All assets made available through Freesound are required to be licensed under either CC0, CC-BY or CC-BY-NC.
Pro Extensive asset information
Each sample has a details page which includes a waveform view, a full-length audio preview, user-assigned tags, author-assigned "pack" grouping, and an author chain ("remixes and sources") for derivative assets.
Pro User review system helps gauge asset quality
Those who have downloaded an asset can give it a rating (5-star system) and optionally a written review. Packages with at least four show their average rating, and total number of ratings. (Packages below the threshold show "Not enough ratings" instead.)
Pro Excellent presentation, organization, and search
The Unity Asset Store is well-presented, with an intuitive category system and effective search. In addition, the requirements to place an asset on the store include providing several standardized graphical and descriptive elements so that individual packages match the same presentation standards as the store itself.
Cons
Con Some assets may have restrictive licenses
Freesound permits uploaders to select the CC-BY license, which disallows the use of DRM, and the CC-BY-NC license, which disallows commercial use entirely. Licenses are prominently displayed on an asset's details page, and represented by a small icon in list views, but there is no option to filter by asset when searching or browsing.
Con Audio samples and sound effects only
Freesound does not host any kind of non-audio asset.
Choice of music is also scant.
Con Unity3D license required to download assets
Though assets may be browsed through the web, they can only be downloaded from within a licensed and registered copy of Unity3D (Free or Pro). However, once downloaded, the Asset Store EULA does not prevent using them in non-Unity projects so long as those projects match the "games and interactive media" description.