I'd like to transit from MacOS to Linux and want to move my data from a Mac to a new machine. What is the best tool to access Mac disks in elementary?
elementary OS is able to read macOS HFS+ disks.
If you want to write to HFS+ disks from elementary OS, you need to install some additional software.
Alternatively, to avoid any possible mess with HFS+ disks being written to by Linux (and if you don't plan to use your Mac drives for booting your Mac) you can reformat your macOS drives to exFAT file system, which has native read/write support in elementary OS, macOS and Windows 10.