https://gitlab.futo.org/keyboard/latinime/-/blob/master/LICE...

It is not open source. They use a custom source available license. There's no way any Android distribution would include it. A layman's reading is that FUTO could claim license violation on account of the distribution accepting donations (non-commercial use only) and there's a weird clause about not accusing FUTO of patent infringement.

Alternatively they could ask FUTO for a commercial license.