* MSCI Asia ex-Japan up slightly after previous session's rally
* HSBC flash PMI awaited for latest clue on China manufacturing
* Australia inflation data could boost RBA rate hike expectations
By Lisa Twaronite
TOKYO, July 24 (Reuters) - Most Asian stock markets edged up in a tentative morning session on Wednesday, while the dollar treaded water, as investors awaited the latest reading on China's manufacturing activity to gauge the health of the world's second-biggest economy.
The HSBC China flash PMI is scheduled to be released at 0145 GMT. Signs that Asia's powerhouse economy is slowing would weigh on equities markets and commodities prices, and might give the U.S. dollar some support.
In recent sessions, reports have suggested that China was moving to support its cooling economy.
Worries of a rapid slowdown in China's economy and plans by the U.S. Federal Reserve to trim its massive bond-buying stimulus later this year have rattled global markets in recent weeks.
"It is well understood by market participants that the ongoing slowdown in China is the result of a government-led effort to shift the drivers of growth away from public investment and to promote private consumption," said analysts at Barclays in a note to clients.
They added that commodities and resources equities are more vulnerable to a slowdown in China than risk currencies.
MSCI's broadest index of Asia-Pacific shares outside Japan added 0.3 percent.
Japan's Nikkei share average edged down 0.4 percent after a two-day rally.
"The overall market may weaken partly because it is slightly overbought and the yen is strong, but individual earnings news is lifting interest in some stocks," said Kenichi Hirano, a strategist at Tachibana Securities.
Japan's export growth unexpectedly slowed in June from a year earlier, government data showed on Wednesday, in a worrying sign that China's slowing economy is hurting overseas demand and could potentially threaten Japan's economic recovery.
In U.S. trading on Tuesday, the S&P 500 snapped a four-session winning streak and retreated from Monday's record closing high, while upbeat results from United Technologies bolstered the Dow, which also touched a record intraday high.
The Australian dollar edged higher against its U.S. counterpart, well above a three-year low set earlier this month, ahead of domestic inflation data at 0130 GMT.
A low reading would boost speculation that the Reserve Bank of Australia (RBA) will cut interest rates next month, which would weigh on the currency.
Yields on U.S. benchmark 10-year Treasury notes rose to 2.514 percent from their U.S. close of 2.507 percent, though still well below a two-year high of 2.76 percent touched on July 8.
The euro was steady at $1.3221, after rising as high as $1.3238 on Tuesday, its highest level since June 21.
Against the yen, the dollar was steady at 99.50 yen, above a one-week low of 99.13 yen touched in the previous session.
The dollar index added about 0.1 percent to 82.015, after it skidded to a one-month low of 81.926 on Tuesday. The index set a three-year high of 84.753 last week.
Commodity markets pushed higher ahead of the China data. Copper added 0.2 percent to $7,049.50 a tonne, while U.S. crude rose 0.2 percent to $108.60 a barrel.
Spot gold remained above the $1,300 an ounce after rallying to a one-month high on Tuesday.