0w-20, 5w-20, 5w-30 or at max. 10w-30 are the recommended engine oil grades by Toyota Motor Corporation Japan, for Toyota Aqua hybrid JDM.
The engine oils grades must meet latest API SN / SN Plus (preferably with RC "resource Conserving"), and / or ILSAC GF-5 criteria. The engine oils must be fully synthetic, from some reputed brand, and 100% genuine and original.
If engine health is perfect, always start from the thinnest recommended engine oil grade, i.e. 0w-20 (and gradually move upwards towards 10w-30, depending on engine health, odo reading, oil consumption, etc.)
Reputed brands in budget-series include: Shell, ZIC, Kixx, Total, Caltx, Chevron, Havoline, Mobil1, etc.
Premium Reputed Brands include: Amsoil, Valvoline, Kendall, Liqui Moly, etc.