Missing products in whole category after import and reindex issue
I have tried to find solution on forum, but all topics are connected with stocks issues.
We have quite big webstore in 6 languages. Database are like ca. 50k of products on each store view. Magento 2.3.5-p2.
The problem is that when we import new products to production store, always all products form some categories are missing. It looks like category would be empty. Problem disapear after reindexer will finish working. But mostly import process takes 40min (products, pictures, translation on each store and prices). Then 20min takes reindexing. For 1h from frontend missed like 20k of products...
How could we import products in live time, when during import, products on the front are missing? Perhabs we have some wrong configuration? Indexer is being running by scheduled. Cron indexer is being running every 1 minutes. We have tried to change it to 60min during import, without success. Also I have thought that magento rebuild index by reindex not all but only new products. Why old products become invisible until reindex during import compleatly new products?
Any idea how to set this up to avoid this problem? It is really negative experience for customer if he go to the category and it is empty...