Please check this article.
VRA - “Send Invite” button is disabled (Greyed Out)
https://help.salesforce.com/s/articleView?id=000395645&type=1
Visual Remote Assistant - Invite button greyed Out
https://trailhead.salesforce.com/trailblazer-community/feed/0D54S00000JgSN7SAN
I am having trouble with the button being grayed out when I log in as a user without using the “Login as” mechanism.
This issue appears to be due to IP address restrictions set in the profile.
以下のページをみると言語はEnglishだけが書かれています。また、Visual Remote Assistantのグループをみても言語設定につては触れられていないです。英語しか選択できないのかもしれません。
https://edo.my.site.com/edo/s/article/Visual-Remote-Assistant