。
He's strange sometimes.
Literal
He [topic-は] sometimes strange [copula-です].
Note that 変 is a na-adjective (formally, a 形容動詞 'adjectival noun'), so it takes だ/です to predicate, not the い-adjective conjugation. 時々 is a frequency adverb modifying the predicate. A textbook-simple SOV-with-adverb sentence.