"Other than that" can be substituted here, but not "otherwise."

"Otherwise" is generally to express consequences to conditional statements (synonymous with "or else"). For example: "Bob had better study for his test, otherwise he'll fail."

It can also be used to mean "differently" or "anything else." For example: "Bob will fail his exam because he didn't study. He shouldn't expect otherwise."

"Other than that" usually means "separately," or "in addition to that" and can't be substituted into the above sentences. It's mostly used between ideas that have no direct connection, or as a final "catch-all" when listing items or actions.

"Other than that" can be substituted here, but not "otherwise."

"Otherwise" is generally to express consequences to conditional statements (synonymous with "or else"). For example:

Bob had better study for his test, otherwise he'll fail.

It can also be used to mean "differently" or "anything else." For example:

Bob will fail his exam because he didn't study. He shouldn't expect otherwise.

"Other than that" usually means "separately," or "in addition to that" and can't be substituted into the above sentences. It's mostly used between ideas that have no direct connection, or as a final "catch-all" when listing items or actions.