Possible to extract multiple key/value pairs (links) from string in CSV and migrate into multiple link field
Here is my solution to solve a similar problem:

temp_data:
  -
    source: data
    plugin: explode
    delimiter: ','
  -
    plugin: explode
    delimiter: '|'
destination_field:
  plugin: sub_process
  source: '@temp_data'
  process:
    field_attr_1: '0'
    field_attr_2: '1'
    field_attr_3: '2'


Hope it helps.

Regards,
 M.