What are the most common Chinese terms for travel power adapters between different international socket and plug standards? Are there more specific terms than “適配器” which is the general word for “adapter”? What about “轉換器”?



English speakers use a variety of terms to refer to these devices. Personally I find "travel adapter" pretty unambiguous and straightforward.
「转换插头」 just as printed on the picture you provided.

Or, less commonly, 「插座转换器」「电源插座转换器」, etc.