WSMPNTXN_XML not found

During the r12 upgrade, when apply the NLS 6678700 patch, it may fails for Template WSMPNTXN_XML not found.

The Oracle support solution is:
User is upgrading to 12.1.3, and this issue is occurring on the 12.1.1 NLS patch, 6678700 (Latin American Spanish)and has $WSM_TOP/patch/115/publisher/templates/US/WSMPNTXN_XML.rtf 120.0.12010000.2 installed.
To resolve apply Patch 7625851:R12.WSM.B to your test instance and then try applying 6678700


However, you may not want to stop your 6678700 patch, so here is something you can do:
Download this patch, both en and your NLS, copy .rtf to us and .xlf to your NLS. then run this:

java oracle.apps.xdo.oa.util.XDOLoader \
UPLOAD \
-DB_USERNAME apps \
-DB_PASSWORD apps \
-JDBC_CONNECTION host:port:SID \
-LOB_TYPE TEMPLATE_SOURCE  \
-LOB_CODE WSMPNTXN_XML \
-APPS_SHORT_NAME WSM \
-XDO_FILE_TYPE RTF \
-TEMPLATE_CODE WSMPNTXN_XML \
-TRANSLATE Y \
-FILE_NAME $WSM_TOP/patch/115/publisher/templates/US/WSMPNTXN_XML.rtf

-TRANSLATE Y is the key

The XDOLoader utility is a Java-based command line program to load template (RTF, PDF, and XSL-FO), XML, and XSD files to the XML Publisher database tables. Use this utility to download files from one instance and load to another.

More details for XDOloader, see Oracle support note:
How To Use XDOLoader to Manage, Download and Upload Files? [ID 469585.1]