Can XMODEL models interface with Real-Number Verilog models?

Yes, you can mix XMODEL models with Real-Number Verilog models.

When you connect xreal-type ports of the XMODEL models with real-type ports of Real-Number Verilog models, you will have to use connector primitives in-between such as xreal_to_real, real_to_xreal, xbit_to_bit, and bit_to_xbit. If you use GLISTER in a schematic editing environment (e.g. Cadence Virtuoso), then the connector insertion is done automatically.

But note that by mixing Real-Number Verilog models with XMODEL models, the overall simulation speed performance may be deteriorated. The Real-Number Verilog models may generate a lot of events (as many as the number of time steps in the simulation!) and those events can propagate into the XMODEL models. You will find that the more models you replace with XMODEL, the faster the simulation becomes.