Given the circumstances you've described, the correct and most favorable filing status for Anthony and Lachelle for the year 2023 would be Married filing jointly.
Since Anthony became a resident alien during the year, he can choose to treat Lachelle as a resident alien as well. This allows them to file jointly and report their total worldwide income for the entire year. Filing jointly typically offers more tax benefits, such as lower tax rates and eligibility for various credits and deductions compared to other filing statuses.
Thus, the recommended filing status is Married filing jointly.