2 Transistor XOR Cell Floating Output Problem
you have not connected the body/bulk connection properly in your schematic.  PMOS to VSS. But that circuit leaves the output node floating for the A=B=1 condition.  Scan through the various solutions here, there is a robust TG version of XOR and XNOR, it uses 4 transistors though.

If you look at all the possible states, you have 2 transistors each in 2 states for 4 possible combinations.  There will always be one combination in which both transistors are off and thus the output node will float.