Well if you turn snap off you can draw in notes of any duration at any position. Then you could turn that into a quantize preset. After that you can just snap to that new preset.
Probably the easiest way to do this even leaves snap on. Make a one bar midi part and open it in the Key Editor. Enter a regular 16th note at the beginning of the measure. The default resolution is 120 ticks per 16th note, or 480 for a quarter note. So to fit 7 notes into a quarter it takes 480 / 7 = 68.57 ticks. Select the note you created and in the info line set its length to 69 ticks. Then hit ctrl-D six times to copy the note. Because of the fractional ticks the last note will be a few ticks too long. Drag its end so it snaps to the quarter note boundary, making it a bit short. Then select all the notes and duplicate them to fill out the measure. Use that midi part to create a quantize preset.
Alternatively you could have made the first note 68 ticks long and lengthened the last note a bit. You could also have distributed the extra or missing ticks between several notes. But that would be more work and your never going to notice that one of the notes is 3 ticks shorter than the rest.
This all sounds more difficult than it is. It took me about a minute to do it (including looking up the resolution in the manual) and about 10 minutes to write the explanation.
You can change the default resolution in Preferences/MIDI to something that divides evenly. But I wouldn’t do that since it will likely create confusion in the future.