Google’s official method does involve an ISO file. The process is as follows:
: Insert a USB drive (at least 8GB) and follow the prompts to "Burn" the recovery image to the drive. Method 2: Direct ISO Download download chrome os flex iso
If you absolutely require a direct image file (a .bin file, which functions identically to an ISO for flashing purposes), you can extract it using official Google repository links detailed below. System Requirements for ChromeOS Flex Google’s official method does involve an ISO file
How to Download and Install ChromeOS Flex: The Ultimate Guide download chrome os flex iso
Google does not give out an official file.