Of the four Gospel accounts, only Luke and John mention anyone having difficulty recognizing Jesus after he had risen from the dead.
Luke (24:13-35) recounts the episode of two disciples on the road to the village of Emmaus on the day of the Resurrection. It wasn’t a case of them not recognizing Jesus because his appearance had somehow changed. We are told “their eyes were kept from recognizing him” until he had explained how the Old Testament prophecies concerning the Messiah were fulfilled by him.
In the Gospel of John, the apostles have trouble recognizing Jesus when they are fishing near the Sea of Tiberias and Christ is standing on the shore (Jn 21:1-14). But we’re told that the boat is at least 100 yards off shore, so it’s not surprising that they didn’t recognize him at once.
Similarly, Mary Magdalene didn’t recognize Jesus immediately outside the tomb until he called her by name (Jn 20:14-16). Perhaps in this instance he was some distance away also. More than likely she was so intent on finding his dead body (“Tell me where you have laid him and I will take him away”) that his risen body escaped her recognition. Mourning, she also may have not looked Jesus in the face until he said her name, and her eyes were full of tears in any event (20:13). And she might have been supernaturally prevented from recognizing him, just as the disciples on the road to Emmaus had been.
Thomas was able to identify Jesus’ body (Jn 20:24-29), and the rich man had no trouble recognizing Lazarus and Abraham even without their bodies (Lk 16:20-24), so we will have no trouble recognizing our loved ones–provided we end up in the same place.