2 Questions I thought of after completing the series

Q.1) If Uchiha-A traps Uchiha-B in an izanami, and Uchiha-B wants to escape, so he uses izanagi to change reality... Then what happens? Q.2) But once B has used izanagi he loses his sharingan.... But as we've seen the Kabuto case, anything that Kabuto does against destiny inside the izanami, time reverts itself (he's trapped in a time loop), so does that mean Uchiha-B would retain his sharingan again and again?