Munoz, 53, who is also the automaker's Chief Performance Officer, has been with Nissan for 15 years. He was recently placed on a leave of absence due to the ongoing probe.
China and other countries place more restrictions on conventional gasoline and diesel engines, auto companies have accelerated the shift to electrification.
With the trade talk outcome still uncertain, failure could quickly reignite pressure on the yuan with some still expecting it to breach the key 7-per-dollar mark on dimming growth outlook.
Japan's Nikkei rose 1.3 percent, while China's benchmark Shanghai Composite and the blue-chip CSI 300 rebounded 1.5 percent and 1.8 percent, respectively.
Financial markets were riding a relief rally on Monday on expectations that face-to-face trade negotiations between delegates from Washington and Beijing, due to start on Monday.