In Mainland China, 质 is always zhi4, the 4th tone.
In the words listed in cantonese.sheik.co.uk/dictionary/characters/1028/?full=true , you can see same [TW] marks (like the following) :
神經質 san4 ging1 zat1 shen2 jing1 [TW] zhi2 [PRC] zhi4
That may be where the zhi2 sound comes from (although some of the words do not have the mark). But I do not have a dictionary from Taiwan to check how it is regulated there.
As for Google translate, it is not a great source for this kind research, and I want to report a bug if I can.
Edit:
Found an online dictionary in Taiwan, and 质 has two pronunciations there:
zhi2 :
[名]
1 事物的根本、特性。如:「特質」、「流質」。《論語.衛靈公》:「君子義以為質,禮以行之。」《史記.卷二四.樂書》:「中正無邪,禮之質也。」
2 人的天性稟賦。如:「資質」。
3 樸實的本性。如:「文質彬彬」。《論語.雍也》:「質勝文則野,文勝質則史。」《韓非子.解老》:「夫君子取情而去貌,好質而惡飾。」
4 形軀、形體。三國魏.曹植〈愍志賦〉:「豈良時之難俟,痛余質之日虧。」
5 箭靶、標的。《荀子.勸學》:「是故質的張而弓矢至焉。」《後漢書.卷六十上.馬融》:「流矢雨墜,各指所質。」
6 古代的一種刑具。《史記.卷九六.張丞相傳》:「蒼坐法當斬,解衣伏質。」
[動]
詰問。《禮記.中庸》:「質諸鬼神而無疑。」
zhi4:
[動]
用財物或人作保證以為抵押。如:「質押」。《戰國策.趙策四》:「於是為長安君約車百乘,質於齊,齊兵乃出。」
[名]
拜見長輩時奉上的見面禮。通「贄」。《孟子.滕文公下》:「出疆必載質。」漢.趙岐.注:「質,臣所執以見君者也。」《史記.卷八四.屈原賈生傳》:「乃令張儀詳去秦,厚幣委質事楚。」