Rashi: In the future, when Hashem will write (sentence) the Goyim for disgrace, He will count the Jews swallowed among them and forced among them, and take them out from amidst them.

Radak: When Hashem wrote [about] the nations that they will have few Chachamim about whom people say "he was born here", He wrote this place (Tziyon) for praise, that there will be many Chachamim. This writing is His decree. This is like "b'Hanchel Elyon Goyim b'Hafrido Bnei Adam Yatzev Gevulos Amim l'Mispar Bnei Yisrael" (Devarim 32:8).

Radak, based on Ibn Ezra: Yispor refers to counting. He knows all born from the nations, and all the Chachamim born in Tziyon, for they are greater than the number of people ¹ .

Radak (7, from Shocher Tov): From the Goyim who will bring Yisrael, He will write them with Yisrael, as if [the Goy] was born there at that time.

Malbim: An individual born in Tziyon, Hashem will count him in the ledger of nations, as if he is a full nation by himself. They are not considered like individuals, rather, like full nations.

Rashi: Hashem will say [about each Jew among the nations] 'he was born from those of Tziyon', and select them for Himself. "V'Gam Mehem ¹ Ekach la'Kohanim la'Leviyim" (Yeshayah 66:21) - from the Goyim who bring [the Jews among them] for a Minchah, I will take those swallowed among them, and there will be among them Kohanim and Leviyim who are not Nochrim. They are revealed in front of Me - "ha'Nistaros la'Shem Elokeinu" (Devarim 29:28).