Hello @Dimitri Brems,
Based on this link, the ASR 900 Series support the configuration for IPSec and you should be able to build the VPN tunnels.
Now I think your question is regarding this link, since it only shows the license scheme for ASR 903 and 907 but doesn´t show any information for the 902. Since this can be a problem with documentation, I would suggest to open a case with TAC and ask for the Licensing Team since you have a concern on this matter.
HTH
Martha