Jazz waltz comping — the 3/4 feel of "Someday My Prince Will Come", "Bluesette" and the Bill Evans trio. Two one-bar figures alternate: odd bars put a chord on 1 and a longer one on the and-of-2; even bars answer with chords on 2 and 3. The bass plays a dotted-half-note feel (root on 1, a fifth or approach note on 3), and the percussion layer is plain quarters.
The feel: a jazz waltz is not "oom-pah-pah". The and-of-2 anticipation does the same job the Charleston does in 4/4, and the second-bar "2, 3" lets the phrase breathe; many players feel two bars of 3/4 as one of 6/4.
Listen for the bar line: because bar 1 lands on 1 and bar 2 does not, the two-bar unit is easy to feel, which is why comping in 3 so often comes in pairs.
Practice: count "1 2& | 2 3" aloud; then move the chords around (1 and 3, or and-of-1 and 3) keeping the bass steady. Voicings, bass line and rhythm are standard practice — no transcribed source.