Welcome! And congrats! An upgrade can drive one nuts ... especially with plugins that might not be compatible with the version one is upgrading to. Been there ... done that! :\
Since the environment check doesn't check addons/plugins, I've a script using moosh that I've called 'checkaddons' that I run to see if there are updates to the plugins.
Looks like:
-----
#!/bin/bash
#
echo 'Add-on listing: ';
cat ./addons.txt;
echo '---------------------';
for i in `cat ./addons.txt`
do
echo "Addon in que: $i";
moosh -n plugin-list |grep $i
done
------
The addons.txt file is nothing more than a text file that list the shortnames of the addons:
Example of addons.txt:
mod_hvp
mod_questionnaire
mod_customcert
Output of script looks like:
Addon in que: mod_hvp
mod_hvp,2.7,2.8,2.9,3.0,3.1,3.2,3.3,3.4,3.5,3.6,https://moodle.org/plugins/download.php/18393/mod_hvp_moodle36_2018113000.zip
Addon in que: mod_questionnaire
mod_questionnaire,1.9,2.0,2.2,2.3,2.4,2.5,2.6,2.7,2.8,2.9,3.0,3.1,3.2,3.3,3.4,3.5,3.6,https://moodle.org/plugins/download.php/18487/mod_questionnaire_moodle36_2018050108.zip
Addon in que: mod_customcert
mod_customcert,2.9,3.0,3.1,3.4,3.5,3.6,https://moodle.org/plugins/download.php/18626/mod_customcert_moodle36_2018120301.zip
I can then acquire the zips via wget and be prepared for 'events' on updates/upgrades of the site.
'spirit of sharing', Ken