Congress has the power (Article I, section 4) to make rules for the election of Representatives and Senators, any state laws to the contrary not withstanding.
I doubt that Congress (or the President) can regulate how State Legislatures appoint their Electors for President and Vice President. The Founders were very careful to exclude the national government from involvement in that process (for obvious reasons).
“✅ Cutting federal funding to states who REFUSE to take steps to secure elections”
They can follow the constitution and the law or lose federal funding.
As Maine’s governor just found out.