Zone 2, mixed modality workout:

40-30-20-10 Calories row (or aerobic machine)
20, 15, 10, 5
Round 1: Air squat https://buff.ly/3O9qA8Z
Round 2: Kettlebell swing https://buff.ly/3HnO1au
Round 3: push ups
Round 4: Pull ups https://buff.ly/3UaAieT
Do 50 cal, 25 squats, 40 cal, 20 squats etc.

Scaling options:
Duration:
S: 1 round
M: 2 rounds  
L: 3 rounds
XL: 4-6 rounds

Intensity/ difficulty:
Row, complete all the rows at Zone 2.

Squat options, basic to advanced:
1. Sit to stand – From a seat.
Arm drive & torso forward rock: Use your arms to generate momentum to aid you standing. Taking out the arm swing makes it harder.  
Start standing makes it easier (stand to sit to stand).
Seat height: Lower the seat makes it harder, higher makes it easier. https://buff.ly/3Ow8yOr
2. Air squat – Just your body weigh. Start standing, don't use an object or target.  https://buff.ly/3O9qA8Z
3. Goblet Squat – Add a weight held at chest height https://buff.ly/3O80Ych

Take out the arm swing makes it harder.