ESP.wdtFeed() in loop

hello, is there a problem if i call ESP.wdtFeed(); in loop so it will execute each time the loop runs.. also in places before delays ?
is ok to disable software wtd and leave hardware at 8sec resets ? what can happen without soft watchdog since it may cause only troubles in my program if it resets

You need to read the documentation for that software, how it is supposed to be operated. Is any example code provided?

Software WDT..... If the code is rigid and handles whatever happens You would likely do well without it. It's much a question about safety, minimum downtime, the eventual need for self recovery.

What is the application?

i have an esp8266 with 4 buttons as the transmitter that sends different values to another board that receives data and trigger some relays based on the button being pressed .I don t want that the board to fail or reset when the relays are on , I can post the codes in here if someone would watch over it
also when the send/ receive function run, i don't know if the loop where they where called move on or waits until the message was send and it got receive confirmation so maybe i have to or not to add some feeds in there. as also the loop should feed it but it doesn't and i get random resets if i disable software wtd and never feed myself

One way is to use a CAN buss communication strategy. In that world each command is valid for a limited amount of time only, a fraction of a second. If the receiver does not get the next command within a certain time the receiver goes to an emergency state, drops relays, stops whatever needing to be stopped.
The demand for the master is to repeat the command as long as the action should go on, at a frequency being higher than the timeout in the receiver..