Senario:

Player A: Has 1 monster on the field.
Player B: Has 0 monsters on the field; Soul Exchange and Jinzo in hand.

Since Soul Exchange lets you tribute your opponent's monster in place of one of your own:

Can Player B activate Soul Exchange and tribute Player A's monster to summon Jinzo, even though Player B has no monsters on the field to be replaced? (if that makes sense)

-

Also, can you tribute your opponent's monster with Soul Exchange in order to summon a Ritual Monster, even if you have no monster(s) on the field/in your hand to be replaced? (if that makes sense)

-

Sorry if these are duh questions, but they've been bugging me for a while, and I've never been able to find good answer to them.

Thanks.

Both are yes. On the Ritual part I guess it could depend on what Ritual monster. If it just for stars then yes. If it has to be a specific card then no.

Yes, "Soul Exchange" can be activated even if the controller using it doesn't have a monster on their side of the field since you are tributing the monster from you hand to the field.
You can use "Soul Exchange" for Ritual Monsters. You would have to activate "Soul Exchange", declare a target for it, then have it resolve.

Yes - Player B may activate and tribute Player A's monster even though there are no monster(s) on Player B's side of the field. The tribute may be used for Tribute summons as well as Special Summons (i.e. Ritual Summons). However, if the monster on Player A's side of the field is something like Spirit Reaper, then the monster is destroyed before it can be Tributed.

Player A: Has Spirit Reaper of the field face up
Player B: Activates Soul Exchange


This is because Soul Exchange targets Spirit Reaper and Spirit Reaper is destroyed by it's won effect. Soul Exchange merely creates a state where the monster may be tributed at any time during the turn.

Player A: Has 4 scapegoats and Reflect Bouder
Player B: Has Canon Soldier

Main Phase 1: Player B activates Soul Exhange on Reflect Bounder
Edit: Battle Phase: Player B Skips Battle Phase (Sorry about that)
Main Phase 2: Tributes Reflect Bounder for Canon Soldiers effect

Hope this helps. :)

Thank you all very much for your quick responses, and for clearing this issue up for me. :)

To clear something else, the above bolded situation cannot happen. "Soul Exchange" forces you to skip your Battle Phase for the turn.