The Q-mini 20 is designed for a fc and esc with 20x20 mount.
?Tip use 5 or 6mm standoffs betweens the esc and fc and not bigger. The space is very tight.
?As you still find itr to close, use a 1 or 2mm spacer under the top plate to rase it a bit.

As you want to use a 30.5x30.5 fc and esc, than it is better to use the Q-mini or the Q-mini 20 with pres nuts.