The Canadians are coming to Bloomington, Minn., promising to build a $1.5 billion fantasyland theme park "equal to Disneyland," a huge shopping complex and a 1-million-square-foot convention center on the site of Metropolitan Stadium south of Minneapolis.

The Chinese, meanwhile, may be about to play in Peoria. The state of Illinois has opened its own trade mission in Shenyang in the People's Republic of China, hoping in part to mine new markets for agricultural and manufactured goods from the Land of Lincoln.

General Motors' Saturn Corp. plant will be in familiar company in Tennessee. Nissan, Toshiba and more than two dozen other Japanese firms have invested $1 billion in Tennessee operations over the past several years, producing 6,700 jobs for the Volunteer State's economy.

Fretting about the nation's record foreign trade deficit but hampered by the overvalued U.S. dollar, state governments across the country are aggressively seeking markets abroad and foreign investment at home as critical ingredients of their economic development programs.

International trade is the theme that runs through the 77th annual meeting of the National Governors' Association, which officially opens here Sunday in the picturesque foothills of the Sawtooth Mountains.

Two-thirds of the nation's 50 states have representatives stationed in foreign countries. Many, like Tennessee, see foreign investment as a way to shift the base of manufacturing in America to their region. Others are entering into regional economic and conservation agreements that leapfrog state and national boundaries.

By 1992, for instance, 10 percent of the electricity used by New England states will be generated by a power plant in Quebec, according to New Hampshire Gov. John H. Sununu (R).

The governors' meeting, which lasts through Tuesday, comes at a time of tension between state governments and two of the nation's principal trading partners, Canada and Japan, both well-represented on the conference agenda.

Canada is America's biggest trading partner ($113.5 billion in 1984), and the $21 billion trade deficit with Canada is exceeded only by the deficit with Japan. Two-thirds of all Canada's exports go to America.

Many governors complain that Canada unfairly subsidizes many of its industries, such as lumber, hogs and fishing, which are pummeling American competitors. New Englanders also blame emissions from Canadian smokestacks for some of the "acid rain" pollutants in their environment.

Canadian premiers from Alberta, British Columbia, New Brunswick, Newfoundland, Nova Scotia, Quebec and Prince Edward Island are scheduled to meet with the governors late Monday.

On Sunday, the governors will hear from Nobuo Matsunaga, the Japanese ambassador. The United States had a trade deficit with Japan of $36.8 billion last year and a deficit of nearly $50 billion is projected this year.

The governors attribute part of that deficit to "protectionist" Tokyo trade policies and are looking to Matsunaga for indications that Japanese markets will be opened more to exports from their states and free trade policies are still viable.

"Otherwise," said Sununu, "I as one conservative Republican governor will bite my tongue and go down to Washington lobbying for some strong protectionist legislation" in Congress.

The governors also are expected to have barbed questions for the only Reagan Cabinet member on their program, Treasury Secretary James A. Baker III.

"Companies in this state -- high-tech companies, traditional manufacturing and otherwise -- are going out there in an international market with a 25 percent penalty on their goods because of an overvalued dollar," said Massachusetts Gov. Michael S. Dukakis (D). "Nothing could be worse than that."

States have turned to international markets as a way of expanding sales of locally manufactured products, mostly from smaller businesses that often cannot obtain federal assistance and might otherwise consider such overseas expansion too costly and too risky.

Many states have found constant efforts to "raid" their neighbors of industries a "zero sum game," according to Deirdre E. Curley, staff director of international trade and foreign relations for the governors' group.

The alternative, in addition to encouraging more local entrepreneurship, is to provide market, language and even financing assistance to home-based firms, or to lure companies from overseas.

Several states have exploited "sister state" relations with overseas countries, while others have capitalized on unique ethnic concentrations -- the Japanese in Hawaii, Scandinavians in Minnesota and Latin Americans in Florida.

Numerous states and municipalities have taken advantage of a 1979 law and set up "free trade zones" where foreign goods can be processed under favorable tariff conditions. New Hampshire has one where Canadian apparel is assembled.

Minnesota Gov. Rudy Perpich (D) said states must make early investments to make sure that the decline of American competitiveness in such fields as textiles, steel and wood does not spread.

That concern intensifies the race to attract high-tech industries among states that have launched sweeping and expensive overhauls of their educational systems.

While many governors appreciate the revitalization brought by foreign dollars, some also say they fear that outsiders may be getting too firm a grip on the American economy.