For LiveEditor pages, go to OptimizePress >> Dashboard >> Global Settings >> Site Footer >> Copyright Information
To add a custom footer copyright text to LiveEditor pages, go to the LiveEditor of the page >> Layout Settings >> enable Footer Area >> enable Extra Large Footer then update.
This will add a row on the footer part of the page. On the page, go to the last row (footer row) then add a text block element for your custom footer copyright text.
For Blog, posts and normal WordPress pages (using OP theme), go to OptimizePress >> Blog Settings >> Brand >> Copyright Notice
