Salat El-Eid can be prayed alone or in a group.

 

So yes if you missed it in a Masjid, you can pray it alone or with family.

 

Just remember no Azan or Khutba when praying alone.

 

Just 2 Rak`ahs with 7 Takbeerah after the Takbeeratul Ihram and 5 takbeerat after standing from the sujud in second Rak`ah.

 

Almighty Allah knows best.