Welcome to Tentmaker's Forum. Very interesting passage you mention for your subject line. Joshua 3:16 right? Or should I say Yeshua 3:16? Sorta reminds one of John 3:16. Romans 5 says that death reigned from Adam to Moses, but with Joshua/Yeshua that river had to back up all of the way to Adam, which if I remember right is the meaning of apocatastasis; a return to an original condition. For those who deny preexistence, that's a mess 'cause if we don't go back to before they say we were cast into futility according to their interpretation of Romans 8, then we're just waiting on somebody else to ruin it for us if we're not talking about a return to a preexistent state; the glory we had with Him before the world began, like Christ Jesus in John 17.
Unless you insert Romans 5's verse about the work of Christ not being like the work of Adam in that although Adam brought death upon all that Christ was to undo, nobody will ever undo the work of Christ by creating a greater expense with their sin than the price of the Blood of Jesus. In that case, then apocatastasis could refer to the Edenic state without the possibility of future death since in Revelation 21 there shall be no more death by the first death of Noah's Flood or the Second Death of the Volcanic fire that'll overtake all that's not written in the Lamb's Book of life that lives in that day, according to 2Peter 3 and Revelation 20. Anyway, everybody else is supposed to be doing the Scriptural exegesis around here except for me, so as always my comments will be brief hoping someone else will have more to add to this. Otherwise, then I may add the other quarter of a million words to this subject. Very fascinating type/shadow passage from Joshua indeed. And again, Welcome to Tentmaker's Forum.