So, since 红 is a verb, it should precede any other attributive. Still, if I Google both phrases, it seems that the latter form is prevalent.
红茶, like 绿茶, (green tea), are particular varieties of tea.
The "red" and "green" do not standalone as verbs describing color but must be compounded with "tea" to indicate a particular variety of tea.
Thus red and green are not verbs but must be read together with "tea" forming compound nouns.
There is therefore only 中国红茶, (Chinese red tea), i.e. a variety of tea popularly known as 红茶, (which is actually black, but who would drink a tea called 黑茶, "black tea"?, which figuratively could mean something "bad" in the tea)
There is no such thing as 红中国茶, meaning "red Chinese tea", which in this case, the 红 would be a verb. You could call it that if you could find a type of tea from China that is actually red in color. But then it would not be "红茶" anymore.
Chinese and English have the different word orders in adjectives.
East China Sea 中国东海
South China Sea 中国南海 (see below)
Simplified Chinese characters 中文简体字
Traditional Chinese characters 中文繁体字
native English speaker 英语母语用户
native Chinese speaker 汉语母语用户
black Chinese tea 中国红茶 [yeah, Chinese think it is red, not black]
By the way, Chinese and English also have a opposite word order in addresses.
Paris, France 法国巴黎
London, England, UK 英国英格兰伦敦
Beijing, China 中国北京
North China 华北
South China 华南
Northeast China 中国东北地区
mainland China 中国大陆
The examples above are normal cases. However, there do exist abnormal cases — English-grammar Chinese.
North America 北美洲
South America 南美洲
East Asia 东亚
Central Asia 中亚
West Asia 西亚
South Asia 南亚
South China Sea 南中国海 (see above)
Those are really English-grammar Chinese, literally translated from English. According to Chinese grammar, they should have been called 美洲北部, 美洲南部, 亚洲东部, etc, but those English-grammar Chinese terms are more prevalent now.