You can jus automatize the execution of the transactions using any tool the allows you to interact with the network.
For instance, this is very easy to do with python and web3py, The only thing you need is a list containing the addresses and a for loop through it to send the transactions.
Step One: Code (I feeled the values with random numbers for the example)
Get the infura link for mainnet and paste in the line 2 instad of 'https://--infuralink'
In accounTarget write the address to which you want to send the ether
In accountList write the addresses from which you will send ether
In privatekeys write the private keys of the addresses in accountList, in order.
save the code in a file with .py extension.
"""
from web3 import Web3, HTTPProvider
w3 = Web3(HTTPProvider('https://--infuralink'))
accountTarget = '0xfba3F929D2116868A77986cE017c91cCee3B03d9'
accountList = ['a905556532f8353195f389824fa34ea8f9719517', '0x7fd094cddd9d824b690c894ddbae63378d9de30b']
privatekeys = ['0x4c0562a69102937d6231471b5dbb6204fe5129617082792ae468d01a3f362318',
'0x7c283a69102937d6231471b5dbb6204fe5129617082792ae468d01a3f362318']
for i in range(0,len(accountList)):
transaction = {
'to': accountTarget,
'value': w3.toWei(1,'ether'),
'gas': 200000,
'gasPrice': w3.eth.gasPrice,
'nonce': w3.eth.getTransactionCount(w3.toChecksumAddress(accountList[i])),
'chainId': 1
}
signed = w3.eth.account.signTransaction(transaction, privatekeys[i])
w3.eth.sendRawTransaction(signed.rawTransaction)
Step two: Requirements.
You need to have python installed, see here how to install python 3.6
Install web3 by doing in the command line (cmd) pip3 install web3
Step 3 run the code
in the command line write python3 filename.py
The code will print the transactionhash, so you can check them
You may try this in a test network first (I test it on rinkeby)
Hope this help.