I tried pulseeffects, but only briefly as it didn’t suit my needs, so not 100% sure how I got it working within Pulseaudio
It looks from your screenshot that sound is getting in to the effects ok, just not getting out
When you were checking Playback tab in Pulseaudio Mixer [pavucontrol], did you have the option at bottom of window set to “Show: All Streams”?
If it is only set to “Show: Applications” you won’t see pulseffects virtual stream to adjust settings you need.
Check Recording tab is showing all streams too - that would probably be place to look at settings to stop microphone audio going to effects
AUR packages won’t always work ‘out of the box’, depends on the individual maintainer.
Comment on AUR page from package maintainer 2017-08-19 suggests there are still some things need work on this package, and it has only been on AUR for 6 months.
This may not be something used by many people on Manjaro so you need to allow a lot more time for getting answers on here compared to the packages maintained in Manjaro repositories