Hi @funack
I am yet to find a solution for this.
As discussed in the old support thread:
Term meta is stored in the wp_options table (as there is no ‘default’ meta table for terms). Each option_name is prefixed with the taxonomy name + term_id
Like this:
category_2_image => 123
I don’t think it is possible to perform a meta query due to the way data is stored.
Perhaps you could look at another term_meta solution?