Foundry is a hobby in itself. It doesn't "just work" for any particular system out of the box. But if you are a tinkering type, you can make it what you want and need. And if you have a lot of time and technical aptitude, you can do some amazing things with it.
While I sing its praises, I don't recommend it for most 5e DMs. I just paid for a two-hour session to have a more experienced and hard-core user help me clean up and reselect modules so I can get things working the way I want them to for my 5e game. That's not a ringing endorsement for the platform for most people.
Yet I can't see myself moving to any other system. Foundry for tactical-heavy TTRPGS and Role for more TotM games.