This is a tricky one to answer, for the answer is yes and no.
No: All the stats and rules will be self contained and, since the original book has no stats for anything, everything you need to play that game will be here. You will be able to use those stats in any 5E compatible game.
However… yes. Because essential information about monsters, creatures, classes, etc will be in the core book.
So I guess I am saying it will depend on how much work you want to put behind the scenes.
To get a flavour of what the rules would be like, my advice would be to check out the Pathfinder rules supplement. Although ours won’t be identical, at least you can see what sort of book you will be getting.
Hope this helps!