How I can round digit on the last column to 2 decimal after a dot using JQ?

Depending on your build of jq, you may have access to some cstdlib math functions (e.g., sin or cos). Since you're on *nix, you very likely do. In my particular build, I don't seem to have access to round but perhaps you do.

def roundit: .*100.0|round/100.0;["Name","Description","Result"],(.hits.hits[]._source | [.acb.item.name, .acb.item.description, (.value|roundit)])    | @csv

Fortunately, it could be implemented in terms of floor which I do have access to.

def roundit: .*100.0 + 0.5|floor/100.0;

I would pass it to awk via pipeline:

jq -r '["Name","Description","Result"],(.hits.hits[]._source |       [.acb.item.name,.acb.item.description,.value])|@csv' yourfile |        awk 'BEGIN{ FS=OFS="," }NR>1{ $3=sprintf("%.2f",$3) }1'

The output:

"Name","Description","Result""Account Average Latency","Generate of last month",210.09"Profile Average Latency","Profile average latency of last month",370.21

Here is your current filter with minor reformatting:

  ["Name", "Description", "Result"], (   .hits.hits[]._source    | [.acb.item.name, .acb.item.description, .value]  )| @csv

Here is a filter which rounds the value column. Note we do this after the @csv so that we have full control over the string

def round:                                                # e.g.    (split(".") + ["0"])[:2]                              # ["210","08691986891395"]  | "\(.[1])000"[:3] as $x | [.[0], $x[:2], $x[2:3]]      # ["210","08","6"]  | map(tonumber)                                         # [210,8,6]  | if .[2] >  4 then .[2] = 0 | .[1] += 1 else . end     # [210,9,0]  | if .[1] > 99 then .[1] = 0 | .[0] += 1 else . end     # [210,9,0]  | ["\(.[0])", "00\(.[1])"[-2:]]                         # ["210","09"]  | join(".")                                             # 210.09;  (   ["Name", "Description", "Result"] | @csv ), (   .hits.hits[]._source    | [.acb.item.name, .acb.item.description, .value]    | @csv    | split(",") | .[-1] |= round | join(",")  )

If this filter is in filter.jq and the sample data is in data.json then the command

$ jq -Mr -f filter.jq data.json

produces

"Name","Description","Result""Account Average Latency","Generate of last month",210.09"Profile Average Latency","Profile average latency of last month",370.21