They don’t have an integration with Roll20 like you can get with DNDB but it works excellently for most other use-cases - if you’re looking to use non SRD content you’ll need to download the relevant expansion files from this spreadsheet and import them:
If you are looking for a free alternative to Dnd Beyond then I recommend Dungeon Masters Vault: https://www.dungeonmastersvault.com/
They don’t have an integration with Roll20 like you can get with DNDB but it works excellently for most other use-cases - if you’re looking to use non SRD content you’ll need to download the relevant expansion files from this spreadsheet and import them:
https://docs.google.com/spreadsheets/d/129gwuo7c2STrgnNs82KDIN3FcxKccRafOk4ykO_imak/edit#gid=1046689729
(sourced from Reddit here: https://www.reddit.com/r/dungeonmastersvault/comments/qa7eqw/all_content_orcbrew_file/)