Trump is going through another impeachment

Trump is no longer POTUS

Article 1, Section 2, clause 5 states that impeachment is specifically for Federal officers and judges

https://constitution.congress.gov/browse/essay/artI-S2-C5-1-1/ALDE_00000030/

Trump is currently none of these things

How is this possible?

Or, if Trump is still POTUS

Article 1, Section 3, clause 6 says that the Chief Justice shall preside over the trial

https://constitution.congress.gov/browse/article-1/

Leahy is presiding, not Roberts

How is this possible?