I changed to iMac JIS keyboard for Mozc, that is on Ubuntu 18.04.

Ubuntu do not like a Japanese Keyboard...

I find few information in the internet
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/usr/share/ibus/component/mozc.xml
<layout>○○<layout> to <layout>jp</layout>

/etc/default/keyboard
XKBMODEL=◯◯ to XKBMODEL="pc105"
XKBLAYOUT=◯◯ to XKBLAYOUT="jp,jp"
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Great! I confirmed match type and print. these are @[;:]
I do not have English Keyboard at going to the office, that is very useful.