If you are switching from Avada (ie, your theme will no longer be Avada), then most likely you will not be able to use the Fusion Builder plugin that Avada apparently comes with. And I’m guessing it’s Fusion Builder just from the directory structure of where your error is being generated.
If you deactivate the plugin, you should no longer have that conflict. I also suspect that whatever code is in getClassAlign() would not actually be viable in your new theme, anyway.
I can’t say that 100% though, because Avada is a paid theme not available from the Themes area of a self-hosted WordPress install. In other words, if you can’t install a theme for free from the admin area, it’s not generally supported here in the www.remarpro.com forums.
Having made that obligatory disclaimer lol, let’s continue.
There is a very popular plugin called Page Builder that similarly does what Fusion Builder seems to do. If you have a site with pages built using Page Builder, and you deactivate that plugin, it seriously screws with your site’s look and feel. The point is that if you deactivate Fusion Builder (if it even works in your new theme, which I hope it will), you will have problems.
The best way to handle all that is to have you post the code from getClassAlign() here. I will take that code and make it to where all it does is pass back what was passed to it, effectively doing nothing but still being available to be called.
For the sake of compatibility, I would put the new getClassAlign() I give you into your new theme’s functions.php. Not every theme has a \framework\ folder, and just about every theme has a functions.php registered into WordPress.
A lot of the above may not even apply since I can’t replicate your old stuff ha, but let me know how it progresses, and we’ll go from there.