Anisotropic stars made of exotic matter within the complexity factor formalism Ángel Rincón, Grigoris Panotopoulos and Ilídio Lopes Eur. Phys. J. C, 83 2 (2023) 116 Published online: 04 February 2023 DOI: 10.1140/epjc/s10052-023-11262-y