Zwaal painted landscapes, portraits, figures in a naturalist style. She was a member of ‘the kring van tekenaars’. Her paintings have been auctioned by Sotheby’s Amsterdam and by Christie’s. Some of her watercolor paintings can be found at the archive of Amsterdam. Some portraits of Ro Morgendorf can be found in the collection of the Jewish Museum in the Netherlands. Pauline shared an atelier with her well respected and liked Jewish colleague Ro Morgendorf at the Reguliersdwarsstraat in Amsterdam.

Zwaag did not leave behind a big oeuvre of paintings, her pieces are considered scarce.