In my opinion, this does not breach the rules. There are very few rules about the placement of the engine itself or it's mounts. Only the intake manifold and throtle has to be inside a line drawn between the top of the roll hoop and the tyres.

I am reading FSAE American rules:
IC1.4.1
"All parts of the engine air and fuel control systems (including the throttle or carburetor, and the
complete air intake system, including the air cleaner and any air boxes) must lie within the surface
defined by the top of the roll bar and the outside edge of the four tires."

However, with an aim of triangulating chassis members and getting a good load path, your mounts could be improved a lot. It depends what other mounts you have, but it seams you are creating a cantilever which is just asking for cracks.