Vocabulary for Sections 2, 3 and 4 (up to unit 24, work in progress), with auto-generated pronunciation.
To exclude units that you haven't studied yet in Duolingo, you can create a filtered deck with a search expression like this:
"deck:Languages::German Duolingo" is:new "tag:re:(s2::u(0[23456789_]|1[0123456789_]|2[0123456789_]).?|s3::u(0[123456789_]|1[0123456789_]|2[0123456789_])|s4::u(0[123456789_]|1[0123456789_]|2[0123456789_]))$"
It'll select all the units except s2u01, thereby effectively excluding them from the study set.
To start learning Unit 2 of Section 2, delete the '2' from the first group '[23..9_]'. This will exclude the cards from the stub deck, and they'll appear in the 'Languages::German Duolingo' deck.
P.S. The first half of the Section 2 grouping does not exactly follow Duolingo's structure.