Can Changelings be detected?
Solution 1:
After reading online this is what I found. (Basically no, detection has no influence on a Changeling.
"Once disguised, the Changeling takes on the enemy's own color and will no longer be automatically attacked by the enemy's units, allowing it to infiltrate enemy territory unsuspected. Changelings cannot be discerned as impostors by any form of detection, nor will the secondary effects of EMP Round reveal their true allegiance. Likewise, a Sensor Tower's Radar ability will not identify the Changeling as hostile after it has morphed. However, if the opponent selects the Changeling, they will be unable to give it orders (since it is not theirs) and the word "Changeling" will appear in place of the unit type that it appears to be." Source: Liquipedia