MoE Routing Testbed: Studying Expert Specialization and Routing Behavior at Small Scale. - Tobias Falke; Nicolas Anastassacos; Samson Tan; Chankrisna Richy Meas; Chandana Satya Prakash; Nitesh Sekhar; M. Saiful Bari; Krishna Kompella; Gamaleldin F. Elsayed (CoRR, 2026)