A:AnswerBoth versions have a 825 GB SSD. This is most likely before accounting for OS and the pre-installed game Astro's Playroom. So less than 825 GB free space.
A:AnswerFrom a hardware standpoint the only difference is the digital edition lacks a disk drive. As far as games, you will have access to all of the same games. Some disc basic games may take up less hard drive space but most will be comparable to their digital versions especially after patches and updates.