Taking advantage of entanglement in B factories to measure the weak phase gamma

B⁰-B ̅⁰ entanglement offers a conceptual alternative to the single charged B-decay asymmetry for the measurement of the direct CP-violating ϕ₃/γ phase. With f=J/ψKL, J/ψKS and g=〖 (ππ) 〗⁰, (ρL ρL) ⁰ the 16 time-ordered double-decay rate intensities to (f, g) depend on the relative phase between the f- and g-decay amplitudes given by γ at tree level. Several constraining consistencies appear. An intrinsic accuracy of the method at the level of ±1° could be achievable at Belle-II with an improved determination of the penguin amplitude to g channels from existing facilities. Other non-CP eigenstates are also analysed as 〖g=D〗^- π^+, D^- ρ^+, in those cases one has to consider together the (f, g) channel with (f, g ̅). We also explore Bₛ⁰-B ̅ₛ⁰ entangled states.