I don't know if it is still required, but your coding should be as follow

nameUA = fields.Char('Name Ua', compute='_compute_name_ukr', inverse='_inverse_name_ukr', readonly=False)

notice the letter "s" in the inverse method, not as typed here with a "c"

i am not sure if it matters, but onchange normally applies to a single record so your onchange method should be

@api.onchange('nameUA')
def onchange_name_ukr(self):
    self.with_context(lang='uk_UA').name = self.nameUA

Follow below steps:

1) Go to

Settings ‣ Translations ‣ Import / Export ‣ Export Translations

leave the language to the default (new language/empty template) # DO NOT CHANGE THIS

select the PO File format

select your module

click Export and download the file

2) Add your translation terms in the downloaded file. i.e. msgstr "" section depending on your translation language

3) change the filename to language_iso_code.po

e.g. for portugese => pt.po

4) create i18n folder under your module and add po file in it.

5) restart Odoo

6) Go to:

Settings ‣ Translations ‣ Load a Translation

select translation language (in my eg. Portugese)

make sure you check this : Overwrite Existing Terms

click LOAD.

DONE