Is it possible to get the URL for google sheet in .dsv format?

Try this (You will probably have to encapsulate the data with quotes.). Here the file is stored in 'test' folder (to be adapted to your project).

const where = 'test' // here the name of folder where you want to record the file
function onOpen() {
  var ui = SpreadsheetApp.getUi();
  ui.createMenu('* Export ... *')
    .addItem('... to .dsv format !', 'createDSVFile')
    .addToUi();
}
// you have to declare a trigger on onEdit
function onEdit(event){
  var sh = event.source.getActiveSheet();
  if (sh.getName()=='mySheet'){
    createDSVFile()
  }
}
function createDSVFile() {
  var sh = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
  var lr=sh.getLastRow();
  var lc=sh.getLastColumn();
  var sep = '|';
  var txt = '';
  for (var i=1;i<=lr;i++){
    for (var j=1;j<=lc;j++){
      txt += sh.getRange(i,j).getValue() + sep
    }
    txt = txt.substring(0,txt.length-1) + '\n'
  }
  var folders = DriveApp.getFoldersByName(where);
  if (folders.hasNext()) {
    var folder = folders.next();
    saveData(folder, 'myDSVFile.dsv',txt);
  }
}
function saveData(folder, fileName, content) {
  var children = folder.getFilesByName(fileName);
  var file = null;
  if (children.hasNext()) {
    file = children.next();
    file.setContent(content);
  } else {
    file = folder.createFile(fileName, content);
  }
  toast('File "' + fileName + '" recorded !')
}
function toast(body, title, timeout) {
  return SpreadsheetApp.getActive().toast(
    body,
    title || "information",
    timeout || 5 // In seconds
  );
}

https://docs.google.com/spreadsheets/d/1h1xXLEOScw2duqydJwtBvZcsfO2vHI05WOf3fojC6VI/copy

To download a specific sheet as a CSV file, replace {key} with the document's ID and {sheet_name} with the name of the sheet to export:

https://docs.google.com/spreadsheets/d/{key}/gviz/tq?tqx=out:csv&sheet={sheet_name}