We had a plan to go to Eritrea around two months ago and we were in Djibouti then. Sad thing is: Eritrea borders both with Djibouti and Sudan are closed, and obviously with Ethiopia too, which means Eritrea is now a completely isolated country for overlanders. To ride it you need to fly or ship there and out again.
Eritrea had serious border disputes with Djibouti recently so there's not much hope this one would open up in near-future. Only probable border that apparently MAY be open again sometime is with Sudan, but Sudan has its own problems right now.
Check the latest updates but don't put much hope on Eritrea opening up.