FYI Filter Forge 14 works in Affinity 3.x (Mac)

Go in to Settings > Photoshop Plugins, select the Filter Forge folder in "Plugin Search Folder," and select "Allow Unknown to be used"
Restart the app and they should be in Pixels > Filters > Plugins

Additional info:
Affinity is a hybrid pixel, vector, page layout app based on Affinity's previous separate products (Photo, Designer and Publisher).
They were bought by Canva last year, made this new hybrid app, and IT'S TOTALLY FREE!
And it works w/ latest versions of Adobe Photoshop and Illustrator files.
(Unless you want Canva's AI tools, then it's extra).

I was recently laid off and lost my access to Creative Cloud apps,. Was going to go back to Affinity, but found things have changed. I've been playing with it for a few days and I think it's powerful, feature-rich, and very intuitive. And that price sure beats Adobe.
And, yeah, they may charge one day, but for now I'm gonna enjoy the ride and redo my stuff.

https://www.affinity.studio/

Here is the fix for windows and it might work on the mac as well. Manual Install