UniProtKB:Q96AZ1 | EEF1AKMT3 | enables | GO:0042054 histone methyltransferase activity | ECO:0007322 IEA | GO_REF:0000116 | RHEA:54192 | 9606 Homo sapiens | RHEA

[ValWood]

UniProtKB:Q96AZ1 | EEF1AKMT3 | enables | GO:0042054    histone methyltransferase activity | ECO:0007322   IEA | GO_REF:0000116 | RHEA:54192 | 9606 Homo sapiens | RHEA

UniProtKB:Q96AZ1 seems to be specific for EEF1A physiologically although it may methylate histone in vitro?

At least the protein is described as
EEF1A lysine methyltransferase 3
Protein-lysine methyltransferase that selectively mono-, di- and trimethylates 'Lys-165' of the translation elongation factors EEF1A1 and EEF1A2 in an aminoacyl-tRNA and GTP-dependent manner. EEF1A1 methylation by EEF1AKMT3 is dynamic as well as inducible by stress conditions, such as ER-stress, and plays a regulatory role on mRNA translation

and no mention of any other substrates.
As far as I was aware its specific for EEF1A

(@pgaudet I don't usually see Rhea issues enough so not sure who to assign to, )