@cerberus2022
IPSec can be set up in one of two modes. The more common mode is "policy-based IPSec", where you have to configure a phase 2 for each subnet pair you want to connect.
However, if you have your subnets sequentially (10.26.1.0/24, 10.26.2.0/24, 10.26.3.0/24) you can also embrace all using a suitable larger mask.
This mode can be used on most IPSec capable devices.
The other mode is "routed IPSec", where you get a virtual gateway IP, to which you can route the respective subnets to the other site.
The only drawback of IPSec is, it cannot be used to forward public traffic to a server at the other site, if you intend to do that.