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A possible encoding as a maxCSP:

variables:

a variable $V_i$ for each number i in $\{1,…,n^2\}$ and a variable $Q$ for the queen.

domains:

the domains of all these variables are the possible cells on the n x n chessboard.

hard constraints:

an alldiff constraint on the $n^2$ $V_i$ variables. for each pair $V_i, V_{i+1}$ of variables, a binary constraint allowing only the pairs of cells being the start and end of a knight move.

soft constraints:

for each prime $p$, a binary constraint involving $Q$ and $V_p$, allowing only the pairs of cells being the start and end of a queen move.

goal:

minimize the number of soft constraints violated.