Connect a Transformer Between VFD and Motor
You can use a VFD that accepts 240 volts, single-phase input and provides up to 240 volts, three-phase output. You will need to connect the VFD output to a three-phase 240 to 480 volt step-up transformer. You could use three single-phase transformers. You can use a 480 to 240 volt step-down transformer and hook it up "backwards." Adjust the VFD so the output only goes up to about 190 volts.
Connect the VFD to the Switch
You can connect the output of the VFD to the switch. You should not operate the switch while the VFD is running, but you can use either switch setting. Using the low-speed setting will give the motor more torque and also prevent having to turn the frequency too low. The transformer may saturate, draw excessive current and overheat if the frequency is turned too low.
A 240:480 V 60 Hz transformer will provide some margin of safety regarding saturation of the transformer with the VFD output. A 240:480 V 50 Hz transformer will provide less margin. A 220:380 V 50 Hz transformer will provide no margin and may force you to operate the motor at a reduced voltage.
Direct Connection To Motor
You could connect the VFD directly to the switch if you adjust the VFD to put out 220 volts at 30 Hz. You could operate the motor up to a little more than half speed that way. You might be able to operate close to full speed with greatly reduced torque.