Functional equation conjecture for zeta functions of arithmetic schemes

Let $\mathcal X$ be a regular scheme of dimension $d$, proper and flat over $\operatorname{Spec}(\mathbb Z)$. Let $A(\mathcal X)$ be its Bloch conductor and let

$$\zeta(\overline{\mathcal X},s):=\zeta(\mathcal X,s)\cdot\zeta(\mathcal X_\infty,s)$$

be the completed zeta function, where $\zeta(\mathcal X_\infty,s)$ is the archimedean Euler factor.

Functional equation conjecture. The function $\zeta(\mathcal X,s)$ should have a meromorphic continuation to all $s\in\mathbb C$ and satisfy

$$A(\mathcal{X})^{(d-s)/2}\cdot \zeta(\overline{\mathcal{X}},d-s)=\pm A(\mathcal{X})^{s/2} \cdot \zeta(\overline{\mathcal{X}},s).$$

This is the expected functional equation for the completed zeta function and is used in the paper to compare the special value conjecture at $n$ and $d-n$. The supplied text gives no evidence that this conjecture has been resolved.