I would like to be able to send directly from OF3 a WhatsApp message.
Writing in the Note area of OF3 the following -> whatsapp://send/ will open the Whatsapp app and launch the Find screen.
Is there any way to paste a phone number or a text (name)…for example:
I use Cardhop for this with dialogue via Shortcuts. You can download the Shortcut here. If I am on iPhone I use the x-callback to Whatsapp directly, on an iPad I use Cardhop. More about communications via OmniFocus is written here