Is it possible for someone else to activate the social security card instead?

Legal analysis: no, only social security cards are allowed, and registration is not allowed. Collection and activation must not be replaced by myself. Except for statutory entrustment notarization.

Legal basis: People's Republic of China (PRC) Social Insurance Law.

Article 4 Employers and individuals in People's Republic of China (PRC) shall pay social insurance premiums according to law, and have the right to inquire about payment records and personal rights and interests records, and ask social insurance agencies to provide social insurance consultation and other related services.

Individuals enjoy social insurance benefits according to law and have the right to supervise the payment of their own units.

Fifth people's governments at or above the county level shall incorporate social insurance into the national economic and social development plan.

The state raises social insurance funds through multiple channels. People's governments at or above the county level shall give necessary financial support to social insurance.

The state supports social insurance through preferential tax policies.