I have meta-mender-community/meta-variscite working for kirkstone [1], but it is pending some enabling from upstream Variscite for the 5.10 kernel [2]. You will need to engage with Variscite sales to convince them to merge my changes. It is clearly not a priority for them.
[1] GitHub - moto-timo/meta-mender-community at variscite-bsp-kirkstone
[2] IMX6: add kirkstone support by moto-timo · Pull Request #17 · varigit/meta-variscite-bsp · GitHub