iOS: Disable WiFi (not just cellular) for specific apps without jailbreaking #

by buying an iPhone in China, which offers an "Apps using WLAN & Cellular" setting in iOS 10.13 and up:

Restrict an iOS app from using Wi-Fi internet
You may not know that iOS 10 has a Chinese "special" Internet access feature
iOS Wi-Fi is turned off for some application and cannot turn on?
7 Steps Apple Could Take to Protect Privacy (#2: Let users disable WiFi per app)
Exclusive feature for Chinese iPhone?
"Apps using WLAN & Cellular" in WiFi feature on American iPhones
How to fix some iPhone apps say no internet connection?
[Request] US iPhones can only disable Cellular data for individual apps. Can someone look into making a tweak to disable WiFi for individual apps as well? (from this post on /r/iPhone)
iPhones bought in China can turn off WiFi or cellular for apps individually, bypassing F2P games’ pop up ads

Extremely disappointing that Apple does not permit this critical privacy and security feature on all iOS devices irrespective of region; its exclusive availability in China is especially surprising given that they usually get the short end of the stick:

Apple moves to store iCloud keys in China, raising human rights fears
After China Objects, Apple Removes App Used by Hong Kong Protestors
Apple's Silence on Chinese Censorship Raises Questions About the Company's Commitment to User Privacy and Human Rights
Apple is Aiding China's Repression
Hong Kong's protest movement keeps getting stymied by Apple
Apple accused of giving Chinese government control over local data
iOS 15: China exempt from Apple 'private relay' privacy feature
In China, Apple Isn’t the Privacy Advocate It Claims to Be
Apple Limits AirDrop in China After It Was Used to Spread Protest Messages