There is no direct way to do this based on the JColorChooser API so we will have to do it old style.
JColorChooser cc = new JColorChooser();
AbstractColorChooserPanel colorPanel = cc.getChooserPanels();
JPanel p = (JPanel) colorPanel.getComponent(0);
The getComponent(0) refers to the first tab of the JColorChooser, in this case the swatch tab. The remove() method is called twice on index number 1 and 2 because 1 is the JLabel while 2 is the recent color history.
That’s it. That should give you a swatch content only tab.