Alibaba is about to get a jolt from its largest rival in Southeast Asia. Sea, the Nasdaq-listed business, is raising as much as $1.5 billion from a new share offering that’s sure to be funneled into its Shopee e-commerce business. Singapore-based Sea said in a filing that it plans to offer 60 million American Depositary Shares (ADS) at a price of $22.50 each.