In this talk, I will present general methods to produce orthogonal polynomial dualities. For models like multi-species ASEP, we start from the $^*$--bialgebra structure of Drinfeld--Jimbo quantum groups. In the case of the quantum group $\mathcal{U}_q(\mathfrak{gl}_{n+1})$, the result is a nested multivariate $q$--Krawtchouk duality for the $n$--species ASEP$(q,j)$. The method also applies to other quantized simple Lie algebras and to stochastic vertex models. For models derived from solutions of the Yang-Baxter Equation, we can make use of the YBE to construct Markov dualities. As a result, we obtain a family of duality functions for the stochastic Higher Spin Vertex Models given by $_3\varphi_2$ functions, which can further be reduced to dual q-Krawtchouk polynomials.
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