I think you should contact the custom development team:

https://wpforo.com/pro-support/#customization

and i need this features for wpforo as new additions or as new pro addon "following pro" :

1. following will send "notification about activities that did by followed user , " in notification Bell" by default , no email send except when a user choose to recieve email in "notifications/following center"

notification bell will make a link with "show more" to open new page with all new notifications when exceed number that be choosen in setting "admin site"

2.  users can choose in Following page (options) for what they recieve , some options by default and others by choosing ,

3. those options includes for example :

recieve notification for following a member that follow new user : by bell notification , or by bell and email , or only show this in "notification center" which is new page that include all notifications from all "wpforo" and wpdiscuz" if they are both installed

4. users can chose email notification for specific actions and activity , i need this to be non choosed by default or some of them , in Wp-admin setting area.

5. Following center settings , for settings that user choose , and Notification center for user to read more notifications if the notifications more than X number .

6. ability for a user to make his username to be followed by "ask to permit / request" and this by option in settings , which protect him from any PM except from his/her following that he already followed and they follow him

7. Notification center "setting" choose to be notified by email or only be "Bell" , and default By "Bell", and Admin can prevent some activity to be send by email to prevent email provider sites to put his site as spammer . ( if there are weekly email option with many notification summery and link to read more ( link to notification center in the site , it wil be great addon).

if this addon can be done in the feature i will be the first customer , and it will be great addition to Wpforo and Wpdiscuz.