Trained on fractional spin (FS) DM21 can capture some multi-reference effects in main group chemistry, such as stretching covalent bonds, though it encounters difficulties at intermediate bond distances. For example, training DM21 on the hydrogen atom with zero polarization ensures the accurate H 2 dissociation limit without breaking spin symmetry. Focusing on dimers, main-group dimers primarily exhibit multireference effects when their bonds are stretched, whereas transition metal dimers display these effects even at their equilibrium geometries. Thus, the difference in the nature of multireference effects between main-group and TMC raises the question of whether DM21's ability to capture such effects in the former can extend to the latter. But, given the known shortcomings of standard functionals like B3LYP in describing multireference transition metals (TM), such as TM dimers, even a far less stringent question arises: Does DM21, which was pretrained on B3LYP densities, perform at least not much worse in this domain than B3LYP itself? Unfortunately, in this paper, we show that the answers to both questions regarding DM21's performance in TMC are negative. While DM21, once it converges, yields accuracy for transition metal compounds comparable (in some cases even superior) to B3LYP, it consistently struggles with SCF convergence. We illustrate the performance of DM21 for TMC in Fig. with beeswarm plots showing errors of B3LYP and DM21 functionals (see the caption of the figure for details). The left panel of Fig. shows DM21's potential to surpass B3LYP in TMC. The data indicate a decrease in median error from 3 kcal/mol for self-consistent B3LYP calculations to 2.3 kcal/mol when DM21 is applied to B3LYP orbitals. Selfconsistent DM21 calculations are in between the two in terms of accuracy with the median error of 2.6 kcal/mol (other error metrics will follow later). The right panel of Fig. gives a more critical assessment of DM21 for TMC as it includes systems that failed to converge with this functional. For these cases, we (arbitrarily) set errors of 50 kcal/mol, a number reflecting the expected upper limit of DFT errors for the considered TMC reactions. When all reactions are considered in the right panel, DM21 evaluated on B3LYP densities remains accurate; however, roughly 30% of the reactions do not reach SCF convergence under DM21. The major convergence issues with DM21 not only limit its practical applicability for TMC but could also render its use impossible in this area.