  Extraplanar tails of ionized stripped gas, extending up to several tens of
kiloparsecs beyond the stellar disk, are often observed in ram-pressure
stripped (RPS) galaxies in low redshift clusters. Recent studies have
identified similar tails also at high redshift and we here present the first
analysis of the chemical composition of such tails beyond the local universe.
Specifically, we examine the distribution of ionized gas metallicity of RPS
galaxies in the Abell 2744 (z=0.308) and Abell 370 (z=0.375) clusters observed
as part of the MUSE-GTO program. We investigate spatially-resolved and global
metallicities in galactic disks and stripped tails, utilizing both a
theoretical calibration through a photoionization model and an empirical
calibration. The metallicity gradients and the spatially resolved
mass-metallicity relations indicate that the metallicity in the tails reaches
up to $\sim 0.6$dex lower values than anywhere in the parent disks, with a few
exceptions. Both disks and tails follow a global mass-metallicity relation,
though the tail metallicity is systematically lower than the one of the
corresponding disk by up to $\sim 0.2$ dex. These findings demonstrate that
additional processes are at play in the tails, and are consistent with a
scenario of progressive dilution of metallicity along the tails due to the
mixing of intracluster medium and interstellar gas, in accord with previous
low-z results. In principle, the same scenario can also explain the flat or
positive metallicity gradients observed in low-mass RPS galaxies, as in these
galaxies the interstellar medium's metallicity can approach the metallicity
levels found in the intracluster medium.
