Hi @Igor_s
Yes, this will work. You will need to configure a Policy Based VPN (crypto map), as currently FTD does not support a VTI.
They are plenty of examples of IOS VPN, but not many examples of a Site-to-Site VPN between FTD and an IOS router. Here is an example of an IOS router crypto map and here and here is another example for FTD Site to Site VPN, between them you should be able to establish a tunnel.
HTH