紙老虎

An early attestation is in the Water Margin as 紙虎:

• 閒常時只如鳥嘴，賣弄殺好拳棒。急上場時，便沒些用，見箇紙虎，也嚇一交。 [Written Vernacular Chinese, trad.]

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  闲常时只如鸟嘴，卖弄杀好拳棒。急上场时，便没些用，见个纸虎，也吓一交。 [Written Vernacular Chinese, simp.]

  From: Shi Nai'an, Water Margin, circa 14^th century CE

  Xiáncháng shí zhǐ rú diǎozuǐ, màinòng shāhǎo quánbàng. Jí shàngchǎng shí, biàn méi xiē yòng, jiàn gè zhǐhǔ, yě xià yījiāo.

  In fair times, you are a big talker and show off splendid martial art. In a pinch, you are so pathetic that in face of a paper tiger, you awkwardly fall into a fit of panic (the adulter hid under the bed, scolded for not dueling the chastiser)

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• 紙老虎

紙老虎

1. (literal and figurative) paper tiger

   • 一切反動派都是紙老虎。看起來，反動派的樣子是可怕的，但是實際上並沒有什麼了不起的力量。 [MSC, trad.]
     一切反动派都是纸老虎。看起来，反动派的样子是可怕的，但是实际上并没有什么了不起的力量。 [MSC, simp.]

     From: 1946, 毛澤東 (Mao Zedong), 《和美國記者安娜·劉易斯·斯特朗的談話》 (Talk with the American Correspondent Anna Louise Strong), 《毛澤東選集》. English translation based on the Foreign Languages Press edition

     Yīqiè fǎndòngpài dōu shì zhǐlǎohǔ. Kàn qǐlái, fǎndòngpài de yàngzǐ shì kěpà de, dànshì shíjìshàng bìng méiyǒu shénme lebùqǐ de lìliàng.

     All reactionaries are paper tigers. In appearance, the reactionaries are terrifying, but in reality they are not so powerful.