For more than a decade, working her way through at least seven passports, she crisscrossed the globe, helping to transform China’s Huawei Technologies Co. into the world’s biggest telecom equipment company—while working to reassure investors, bankers and governments that Huawei can be trusted.

But when she landed in Vancouver on Dec. 1, Meng Wanzhou, Huawei’s finance chief and the daughter of the company’s reclusive founder, became the public face of a bitter battle unfolding across multiple continents.