Many owners run an EA on more than one account: a personal account and a funded one, accounts at two brokers, or several accounts at different risk settings. It is straightforward, and the problems that arise are the same few every time.
Licensing
An EA bought through the MQL5 Market is licensed for a stated number of activations, each tied to a computer, and the platform enforces it. An EA sold directly may be licensed per account, per computer or per owner, and the terms should say which. Running beyond the licence usually stops the EA silently, and it is worth confirming the limit before assuming a second VPS will work.
Identical trades
The same EA at the same settings on two accounts at the same broker will place the same trades at the same moments. That is expected and, for most purposes, fine. It matters in two situations. Some prop firms restrict identical trading across accounts they fund, and it is their rules that govern. And two accounts at the same broker taking the same trade at once are, from the broker's side, one larger order, which can affect fills on thinly traded instruments. Some EAs offer a setting that varies entries slightly between accounts so that they are not identical. Where that exists, its purpose should be understood before it is used.
Resources
Each account needs its own MetaTrader 5 instance, since one platform connects to one account, and each instance needs memory and processor time on the VPS. Two or three instances run on a modest server. Ten do not. Each instance also needs its own charts open for the EA, and its own copy of the settings.
Record keeping
Keep the settings file for each account with the account number and the date, since different accounts often run at different risk settings and the records are not comparable without that. If the accounts are verified with a third-party service, connect each separately from its start date.
An owner runs the EA on a personal account at the medium setting and a funded account in prop mode, at the same broker, on one VPS with two platform instances. In the first month the personal account takes 28 trades and the funded account 24, because prop mode's news filter blocked four. The results differ, as expected, and the two settings files, labelled with the account numbers, explain why. In month three the owner adds a third account at another broker, and finds two of the EA's markets are not offered there. That record differs for a reason that has nothing to do with the settings.
Multiple accounts are the same EA with the same evidence behind it, run several times, and the main risk is administrative: mismatched settings, a licence limit, a VPS without enough memory, or a rule at a prop firm that the owner did not read. Set each account up deliberately, label its settings, and treat each record as its own. The trades will differ between accounts, sometimes a little and sometimes a lot, and the reasons are all on the page about brokers.