Mainland markets up
China's Shanghai Composite index nudged up 0.5 percent in rangebound trade, as investors stayed put on the sidelines ahead of the week-long National Holiday which begins on Thursday.
Traders are also likely eyeing the release of China's purchasing managers' indexes (PMIs) on Thursday, that will shed light on the state of the country's all-important manufacturing sector.
For the quarter, the Shanghai bourse plummeted 34.1 percent while chalking up three straight months of losses.
Among gainers, Great Wall Motor powered up by the daily maximum allowable of 10 percent, while other carmakers such as SAIC Motor and Dongfeng Auto charged up 4 and 1.1 percent respectively, following news that Beijing has decided to halve sales tax on small cars from Thursday. Shenzhen-listed Changan Automobile Company jumped 10 percent.
In other news, China's State Council issued guidelines to encourage deeper links between online businesses and bricks-and-mortar stores on Wednesday, marking another sign that Beijing is shoring up its support for the economy.
Among the other indexes, the blue-chip CSI300 Index notched up 0.8 percent. By contrast, small-caps underperformed with the smaller Shenzhen Composite ticking up 0.3 percent amid choppy trade, while the start-up ChiNext board eased 0.5 percent.
In Hong Kong, the Hang Seng index recovered lost ground on Wednesday, up 1.6 percent.
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ASX leaps 2.1%
Australia's S&P ASX 200 index moved away from Tuesday's two-year closing low, thanks to advances among banking heavyweights and miners.
Commonwealth Bank of Australia led gains in the banking sector, surging 3.7 percent. Investment firm Macquarie Group climbed 2.2 percent and QBE Insurance gained 1.5 percent.
Market bellwether BHP Billiton rose 2.8 percent, clawing back some of Tuesday's steep slump. Rio Tinto and Fortescue Metals also advanced 4.5 and 9 percent respectively, as bargain hunting and short-covering bets helped to offset weaker iron ore prices overnight.
However, energy producers posted a mixed performance. Santos and Oil Search remained mired in the red, down 7 and 1.1 percent respectively, while Woodside Petroleum gained 2.7 percent.
Shares of Origin Energy halted trading on Wednesday after the power and gas retailer said on Tuesday that it would raise $2.5 billion Australian dollars ($1.8 billion) from a sale of new shares, sell assets and cut its dividend to shore up its balance sheet.
The Sydney bourse lost 12.4 percent during the July-September period.
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Kospi gains 1%
South Korea's Kospi index reversed losses to finish in positive territory.
Earlier at the open, the Seoul bourse fell as much as 1.4 percent to a near three-week low, as it played catch-up to its regional peers after being shut for the previous sessions due to the Chuseok holiday.
For the quarter, the bourse slid 5.4 percent to chalk up its sharpest quarterly percentage fall since June 2013, Reuters data showed.
The bourse's top two weighted stocks Samsung Electronics and Hyundai Motor rebounded more than 1 percent each, but steelmaker Posco held on to a near 2 percent loss.
Indian markets up
The S&P BSE Sensex Index and the 50-share Nifty index gained nearly 1 percent in early trade, a day after the Reserve Bank of India (RBI) lowered its policy interest rate by a wider-than-expected move of 50 basis points.
Analysts at Morgan Stanley say another rate cut of 25 basis points is still on the cards amid cooling inflation in Asia's third-biggest economy.
"At the beginning of the year, we made a call that the RBI would be able to cut interest rates by a cumulative 150 basis points, based on our view that consumer price inflation would decelerate on a sustainable basis, therefore providing the room for the central bank to cut," Chetan Ahya and Upasana Chachra, economists at Morgan Stanley, wrote in a note.
"The decision by the RBI to cut rates by a larger than expected 50 basis points means that it has now cut interest rates by 125 basis points since January 2015," they added.