Touch Bar MacBook Pro models have non-upgradeable SSDs, seemingly under-sized batteries - 9to5Mac
Amazon.com: Sintech M.2 NVMe SSD Adapter Card for Upgrade 2016 2017 13" MacBook PRO A1708 Non-Touch Bar Models(Only For Late 2016-Mid 2017 Year) : Electronics
Photo tutorial: Upgrading a MacBook Pro with an SSD
Entry-level M2 MacBook Pro has a slower SSD - 9to5Mac