My proof of concept is close to what you are asking, but not exactly the same.

If we replace Bob with AKA Profiles, and Alice wants to attest she lives in Germany she could go to:
https://get.akaprofiles.com/njump/naddr1qqt8wkrk29xk7ujztpqnwu62we5xk53kfq656dgzyrkm4aaey4raej2rn90ufkevka7d0g3vxj25z7dfnnqvp59vhnrq2qcyqqq82wgt5ph68

Based on her IP address, AKA Profiles would award Alice a GEO Location badge with her current Country, Region, and City. 

Any app / person then who trusts AKA Profiles as an issuer, could verify Alice has been awarded a GEO Location badge with country: Germany.

For P2P attestation of any event, there would need to be an "attestation" kind,  where the event pubkey is attesting that events referenced in the e tags are true.