If your MCU supply voltage is 3.3V you can do it with no components other than a couple of resistors. It is important that the sum of the LED voltages is greater than 3.3V or they will come on even when the MCU doesn't want them to.

If you want one or the other to always be on then that constraint doesn't apply

Set the MCU to one to light D1 Set the MCU to zero to light D2

Set the MCU to hi-z to turn both off

^{simulate this circuit – Schematic created using CircuitLab}

If your MCU supply voltage is 3.3V you can do it with no components other than a couple of resistors. It is important that the sum of the LED voltages is greater than 3.3V or they will come on even when the MCU doesn't want them to.

If you want one or the other to always be on then that constraint doesn't apply

Set the MCU to one to light D1. Set the MCU to zero to light D2.

Set the MCU to hi-z to turn both off.

If you want both on simultaneously toggle the MCU output at 1kHz or so.

^{simulate this circuit – Schematic created using CircuitLab}