Just tested these out and the all fit in Frunk:
Baby Jogger City mini GT 2 (remove rear wheels - easy)
Britax B Lively (remove rear wheels - easy)
Britax B Clever ( remove rear wheels easy)
Baby Jogger City Tour (No wheel removal)
Thule Spring 20 (No Wheel Removal)
Out of all these the Baby Jogger City Mini GT2 is great because it’s practically a full size stroller compared to the rest of the list.
Hope this helps !