Williams, 37, was beaten by her sister Venus 4-6 6-3 10-8 in an exhibition match in Abu Dhabi on Thursday.
The 23-time Grand Slam champion subsequently refused to discuss her confrontation with umpire Carlos Ramos in September's final in New York.
"I don't avoid anything," she said.
"I just don't have time to talk about that.
"I talked about it, everyone talked about it for months and months and months and it's best to move on to bigger and better things."
Williams got a code violation for coaching, a penalty point for racquet abuse and a game penalty for calling the umpire a "thief" in during the loss to Osaka.
She later accused him of sexism and was fined $17,000 (£13,450) for the code violations.
Speaking at the Mubadala World Tennis Championship, Williams said equalling Margaret Court's record of 24 Grand Slam titles was a "significant" goal for 2019.
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