keyremap

private.xml

<?xml version="1.0"?>
<root>
    <item>
        <name>Switch Input Source</name>
        <appendix>Use the right Option key to select the next input source</appendix>
        <identifier>private.switch_input_source_with_right_option</identifier>
        <autogen>--KeyToKey-- KeyCode::OPTION_R, KeyCode::SPACE, ModifierFlag::OPTION_L</autogen>
    </item>
    
    <item>
        <name>Switch Input Source</name>
        <appendix>Use the right Command key to select the next input source</appendix>
        <identifier>private.switch_next_input_source_with_right_command</identifier>
        <autogen>--KeyToKey-- KeyCode::COMMAND_R, KeyCode::SPACE, ModifierFlag::OPTION_L | ModifierFlag::COMMAND_L</autogen>
    </item>
</root>