K2 DataSets plugin will help you to create multiple sets of K2 extra fields for the same K2 item, where original K2 only support one extra fields group for a specific item.
Installation & Upgrade: AutoMeta for K2 installation and upgrade is done from Extension Manager like other Joomla! extensions. It is installed as K2 plugin inside the plugins/k2 directory. Make sure to Enable/Publish the plugin from Plug-in Manager.
Installation & Upgrade: MEFG installation and upgrade is done from Extension Manager like other Joomla! extensions. It is installed as K2 plugin inside the plugins/k2 directory. Make sure to Enable/Publish the plugin from Plug-in Manager.

MEFG for K2

Multiple Extra Fields Groups (MEFG)  for K2 This is a very useful K2 plugin, which enables administrators of websites powered by Joomla and K2 to assign more than one K2 extra fields group to a K2 category.
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Autometa for K2

AutoMeta for K2 AutoMeta for K2 is a plugin to automatically generate meta keywords and description for K2 items from item title, category, tags and extra fields.
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Chained Fields for K2

Chained Fields for K2 It is a package to enable creating chained fields in K2 item edit form.
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