Line-only 6in/2out bus-powered USB interface/mixer for synths only?

Need an audio interface or USB mixer only for getting 3 balanced stereo line level pairs (i.e. 3 synths) into Akai Force and outputting stereo. Class compliant USB audio is a must, MIDI out would be a nice plus but not necessary, USB bus powered (USB-A, not USB-C) is a large plus. No mic or instrument related stuff like preamps or fantom power is needed, I would even prefer not to have it. Doesn't need to have a super high input resolution or high end ADC and mediocre audio output quality is totally ok. Has anyone been in the same or similar situation and found a nice solution?