LaBella Rx series nickels have worked well for me on a non-Alembic bass with Alembic electronics (signature package). They’re round wound, but the outer wrap feels quite smooth. Just be sure to measure your string length, because you might need super-long scale for your instrument.
Most recently, I’ve been trying DR Dragon Skin+ Quantum Nickels on a couple of my Alembics, and I really like them so far. The coating takes just a bit of the edge off, which works particularly well for one of my basses.