Can i see intermediate zoom level for object?
For example: https://www.openstreetmap.org/relation/2099216#map=6/68.036/35.464 , if i set zoom level 6 it’s too small, on level 7 - too big.
Maybe there is a way to view the intermediate scaling result?
No. Image tiles are pre-computed for each zoom level.
The only ways of getting a custom level are to run your own rendering tool chain against the OSM (vector) map, or to use a vector format, scaled to a standard zoom level to establish the text size and the level of detail, and then rendered to the exact final size you want.