Please give more details / screenshots because I don't understand where to look fo a problem nor how to recognize I will have found the problem you are mentioning.

Yandex answer me sitemap do not conform not found index of sitemaps…

When you make multiple blog you have one sitemap by blog but where are globale index of sitemap ?

1. Please send a screenshot of the exact and complete message from Yandex. We need to see what it expects.
2. You can create various sitemaps https://b2evolution.net/man/make-a-site-map
3. If you want Yandex support out of the box, Please send a screenshot of the exact and complete message from Yandex.