EDIT: As of mid-February 2020, the following method has seemingly ceased to work as described. It is unknown at this time what has changed to prevent it, but the "Sending Gift..." dialogue no longer pops up as before, it just goes straight to the notification of the servers being offline. I'll leave this solution up for now in case this is somehow only a temporary issue and people want to give it a try again later. If some months down the road it still isn't working, I'll delete it then. Sorry, everyone.
It's been recently discovered that this achievement is obtainable once again by utilizing a simple workaround to trick the game into believing you've successfully contacted the now closed Ubisoft servers.
There is no need to remove friends or block followers, as stated by the other solutions. Once you've played a short time, and have acquired some Oculi through looting a few chests, you're ready to begin. Follow the steps below exactly and you shouldn't have any problems unlocking this achievement.
1. Press the
button and select Oculi from the options.
2. Choose any of the three equipment slots to see your available Oculi.
3. Highlight the Oculi you wish to give away and press
to Gift it.
4. Choose a friend to send the chosen Oculi to and press
to Confirm.
5. Be ready to pull your network cable from the back of your console and press
to Confirm once again.
6. Immediately upon seeing the "Sending Gift..." dialogue box, pull the network cable and wait until the process completes.
7. On the next confirmation box, press
once more to acknowledge your Oculi was sent.
8. Plug your network cable back in to your console and the achievement will unlock.
Per
jGuiiLe this can be done with a wireless connection as well. In step 6, power off your router when "Sending Gift..." displays and power it back on in step 8.
If anything seems unclear, please comment and I will try to elaborate. Good luck.
Note: If you're starting a new game and don't want to hunt down any chests, you can purchase some Oculi from the uPlay app if you have any points to spare. You get 3 for 10 points, so you'll have 3 effortless attempts at this achievement.