Great responses so far from the Monks, but I didn't see cpan's autobundle mentioned, so here it is, in case you find it useful.

The following command will bundle all of your installed distributions into a single module file that you can then transfer over to any other system, and unbundle it, which installs all of those modules on the new system. It keeps versions and everything.

perl -MCPAN -e autobundle
[download]

Output displays all of the modules as it bundles them, then at the end upon success:

Wrote bundle file
    /home/spek/.cpan/Bundle/Snapshot_2017_08_26_00.pm
[download]

You can then back up, or transfer that file to another system, and install all of those modules with a single command. Copy the file into your .cpan/Bundle directory on the new system, wherever that may be. Note the lack of the .pm file extension here:

perl -MCPAN -e 'install Snapshot_2017_08_26_00'
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