Assume you have the following two options:
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You can travel in time freely (past and future) but your point in space stays fixed.
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You can travel in space freely (teleportation at will) but time passes for you like for everyone else.
Let’s assume for the sake of the argument that the power is safe to use. You don’t die just because you traveled into a moment in time where your current location would kill you, it would warn you about that first.
If your decision includes any other assumptions, just mention them.