[gjrq]

Best one I know of as a direct replacement is AWS PALACE: https://awslabs.github.io/palace/stable/

Of course, you have to interact with the solver through JSON files and provide your own initial mesh. They recently added adaptive refinement but I don't know how well it works. Given what Ansys charges for an HFSS seat though can't complain!

[amelius]

Wow, is there a Kicad script for generating input for this tool based on a pcb layout? That would be awesome!