The first part of the question attracts a ‘No’ answer while the second part is a copied response as follows:

“10 ways China is quietly working behind the scenes at the Qatar World Cup

One: World cup buildings are getting green electricity from a next generation power station which harvests only solar energy, built by the Power Construction Corporation of China.

Two: People are taken where they need to go in a fleet of 888 fully electric buses, made by Yutong Bus, a Chinese firm that has quietly become, as far as I can tell, the world’s biggest bus maker.

Three: The main stadium was built by China Railway Construction Corporation: that’s the firm that pops up in Africa and Europe and around the planet, known for its extraordinary ability to create infrastructure in difficult environments.

Four: What’s a sporting event without souvenir merchandise? It’s estimated that almost 70 per cent of World Cup related goods, from footballs to flags to jerseys to whistles, came from a single location in China, a southeastern city called Yiwu.

Five: A purpose-built extra-large reservoir is providing clean drinking water for sports people and fans. It was constructed by Gezhouba Group, from Wuhan.

Six: The stadium-building operations needed huge amounts of heavy equipment, from massive earth movers to cranes – nearly 100 of these were supplied by China’s Sany Heavy Industry, one of the world’s biggest construction firms.

Seven: The most innovative venue is Qatar’s Stadium 974, which can be disassembled and reassembled anywhere. Designed by a Spanish architect, the 974 building blocks were made by China International Marine Containers.

Eight: Notice all the LED floodlights everywhere? They come from the Unilumin Group of China.

Nine: Most people say airconditioners are a must for survival in that environment – and China’s Midea Co supplied 2,500 aircons for the event.

Ten: Last but not least, this is the most expensive sporting event in world history, and needed a lot of support from businesses. Nineteen China firms signed up to sponsor the event.”

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After your long sermon,the answer is No they are not participating and we Don't care about their extraordinary building capacity.
Las Las majority of the labour force that did the main job were not from China.