I have only been to a couple.
Please add to this list with a bit of a description
Sunnyside - Mornington Peninsular between Mornington & Mt Eliza. A bit of a walk 500m along the beach to your right and around the rocks. Nice quiet bay beach. Well attended.
The Oaks - South Gippsland between Cape Paterson & Inverloch. A bit of a walk down steps and a path go to your left and walk around the point on the rocks. A small quiet sandy cove but very rocky in the water. Bathe in the shallows, but don’t plan on swimming.