The pkg link for the py35-borgbackup is not listed when searching for the pkg within the jail:
$ pkg search py35
py35-Babel-2.3.4_1 Collection of tools for internationalizing Python applications
py35-Jinja2-2.8_1 Fast and easy to use stand-alone template engine
py35-MarkupSafe-0.23_1 Implements XML/HTML/XHTML Markup safe string for Python
py35-PyX-0.14.1 Python package for creating encapsulated PostScript figures
py35-aiohttp-0.21.2 HTTP client/server for asyncio
py35-asciinema-1.3.0_1 Tool for recording and sharing terminal sessions
py35-asyncio-3.4.3 Reference implementation of PEP 3156 (Asynchronous IO)
py35-atspi-2.18.0 Python3 API for the D-BUS based SPI framework
py35-bsddb3-6.2.1 Python extension module for BerkeleyDB 3 and 4
py35-cairo-1.10.0_3 Python 3 bindings for Cairo
py35-chardet-2.3.0_1 Universal encoding detector for Python 3
py35-click-6.6 Python package for creating command line interfaces
py35-cssutils-1.0.1,1 CSS Cascading Style Sheets library for Python
py35-dbus-1.2.0_1 Python3 bindings for the D-BUS messaging system
py35-diffoscope-59 In-depth comparison of files, archives, and directories
py35-dnspython-1.15.0 DNS toolkit for Python
py35-dugong-3.5 HTTP 1.1 client module designed for RESTful protocols
py35-gdbm-3.5.2_4 Python bindings to the GNU dbm library (Python 3.5)
py35-gobject3-3.18.2 Common files for the Python bindings for GObject
py35-gstreamer1-1.8.0 GStreamer python 3 bindings
py35-hunspell-0.4.1 Python module for the Hunspell spellchecker engine
py35-jsonschema-2.5.1 JSON Schema validation for Python
py35-kyotocabinet-1.22_1 Python binding of kyotocabinet
py35-libarchive-c-2.2 Python interface to libarchive
py35-libnacl-1.4.4_2 Python bindings for libsodium/tweetnacl based on ctypes
py35-libpeas-1.16.0 libpeas Python 3 support
py35-libxml2-2.9.4 Python interface for XML parser library for GNOME
py35-lxml-3.6.0 Pythonic binding for the libxml2 and libxslt libraries
py35-mutagen-1.36 Python-based audio metadata tag reader and writer
py35-mysqlclient-1.3.8 MySQL database connector for Python
py35-netifaces-0.10.4_1 Getting network addresses from Python 3
py35-nose-1.3.7 Discovery-based unittest extension
py35-pager-3.3_1 Terminal/console pager module
py35-pillow-3.1.1_1 Fork of the Python Imaging Library (PIL)
py35-postgresql-1.1.0_3 Python 3 compatible PostgreSQL database driver and tools
py35-psycopg2-2.6.2 High performance Python adapter for PostgreSQL
py35-py-1.4.32 Library with cross-python path, ini-parsing, io, code, log facilities
py35-py3dns-3.1.1 Python 3 DNS library
py35-pybugz-0.13 Python command-line interface to bugzilla
py35-pygraphviz-1.3.1 Python interface to GraphViz agraph
py35-pyicu-1.9.4_1 Python extension wrapping IBM's ICU C++ API
py35-pylast-0.5.11_1 Python3 interface to Last.fm
py35-pylru-cache-0.1.4 LRU cache for Python
py35-pytest-3.0.5 Simple powerful testing with Python
py35-pytest-asyncio-0.5.0 Py.test plugin providing fixtures and markers for asyncio
py35-python-magic-0.4.10 File type identification using libmagic
py35-pytz-2016.4_1,1 World Timezone Definitions for Python
py35-requests-2.11.1 HTTP library written in Python for human beings
py35-setuptools35-32.1.0 Python packages installer
py35-skog-0.1.0 Generate visual dependency trees for FreeBSD ports
py35-sleekxmpp-1.3.1_1 XMPP Library
py35-spdx-2.3.0 SPDX license list database
py35-spdx-lookup-0.3.2 SPDX license list query tool
py35-speech-dispatcher-0.8.6 Python bindings for Speech Dispatcher
py35-sqlite3-3.5.2_7 Standard Python binding to the SQLite3 library (Python 3.5)
py35-threema-msgapi-2.1.8 Threema Gateway Message SDK for Python
py35-tkinter-3.5.2_6 Python bindings to the Tk widget set (Python 3.5)
py35-vcversioner-2.16.0.0_1 Use version control tags to discover version numbers
py35-xdg-0.25_1 Python 3 library to access freedesktop.org standards
py35-xist-5.23 XML-based extensible HTML generator
py35-yaml-3.11_2 Python YAML parser
However if I perform the same search within a FreeBSD install located within a VB system running on a different computer, the py35-borgbackup is listed. It's as if I'm not getting an accurate pkg list from within the FreeNAS jail
I understand the problems of mixing ports and packages. I'd prefer pkgs if possible, and as of right now, I'm not sophisticated enough to really configure a lot of the make parameters with the ports packages and usually just accept the defaults.