Hello,
After reading your post, I would like to clarify some things.
Site-to-Site VPN is used to connect two peers, example Firewall-to-Firewall, Router-to-Router, Firewall-to-Router.
while on the other hand, Cisco Any Connect is used to connect Clients from any where to internal network.
In Site-to-Site VPN you do not choose users, you only choose the two peers that they need to establish a connection. In the Crypto map you can specify to what they can have access. This is usually good to use if Users are being connected from one office to the other. Make sure to use correct NAT and follow the same Encryption, Authentication, Deffihelmin group, and Hashing, also to mirror the Access lists between the two sites.
Cisco Any Connect is used if the client is connecting from his laptop/computer from any where to access company resources. If you are using this type of VPN you can create a Group policy and put the users you want in it (you can create users on local database,or use an Authentication server with Radius), and just reference to the same group policy in each Any connect VPN you create. You can also install the Cisco any connect software remotely the client Stations by them just accessing the link you provide ( I advice you to check the CCNA Security Guide to see the process it is clearly indicated)
Hope this helps,
Best Regards,
