What Is A Replacement Player In HBD and How Many Games Would A Team of Replacement Players Win?

Since I'm starting a rebuild with a new team and employing (very cheaply) a fair number of players who will be useful to me but would not make the roster of a good team, I'm wondering how the concept of "replacement players" applies in HBD.

Obviously, "replacement value" and "wins above replacement" have come to be kind of a gold standard in the evaluation of rl Major Leaguers.   I don't know how it's calculated and don't care to get into the statistical weeds of the idea, but I do have a few questions about the basic application of the idea in HBD.

Specifically:

1.  What is a prototypical "replacement" player in HBD?

Is it a "4A" player (whatever that is)?  Is it a player who has not been signed during the 4-day formal FA process?  Is it a player who hasn't been signed by the start of the season?

2.  How many games would a team of replacement players win?

Maybe there's a way to put a number on this other than anecdotally...I don't know what it is.   I suspect it's higher than we all think, as the turnarounds I've taken on and populated with bargain-bin FA's have always seemed to win 65+ games and usually 75+ games.

Tossing that question out because a turnaround I took over in another world had a bunch of players on the ML roster that shouldn't have been above High A.  The team won 38 games the year before and the previous owner was appropriately booted, but I'm wondering if some kind of application of the concept of replacement players could be a better determinant of "tanking" than straight wins and losses (although I think wins and losses is a pretty good measure).

Interested in all viewpoints...comment here or put on world chat or tc or whatever - thanks.