'Overwhelming' can also mean "most". For example
"According to the chart, the overwhelming majority preferred online books" (= most people).
"The overwhelming majority of teachers are overworked and are underpaid". (=most teachers).
'Overwhelming' is also a Present Participle and can be a high-level linking word.
'Overwhelmed' is a Past Participle, and can also be used as a high-level linking word.
Members Academy - check out the Present/Past Participle Linking Word lesson here.