The bug
Baby zombified piglin spawned while right-clicking an adult zombified piglin have no weapon.
Linked issues
is duplicated by
relates to
Attachments
Comments

This could be intencional see https://bugs.mojang.com/browse/MC-172123?focusedCommentId=633964&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-633964

In 20w12a
In 20w18a
Should be forward-resolved to MC-182903
in 1.15 pre 6