Chosen aspects of twisted brane geometry in the Wess-Zumino-Witten models of type A_2n shall be discussed, both classical and stringy, in reference to a class of coideal subalgebras of Drinfel'd-Jimbo quantum groups known as twisted orthogonal quantum groups. An explicit relation between the two families of algebras, together with a realisation of the latter as (twisted) Reflection Equation Algebras shall be invoked to emphasise the role played by them in a compact algebraic description of quantum twisted branes on SU(2n+1) in the framework of R-matrix Reflection Equations and associated quantum group geometries.