Yeah if you don't have a big installation, you can just re-make the packages on Blesta, then install the support module. And then just import everything. But your services will need to be done manually as-well.
So it's a bit time consuming but if you want to get off that system like I did, Import from WHM** to Blesta 2.5, then import from 2.5 to Blesta 3.0.