For multiple Rithmic prop firms, we set up multiple VPS in a local network so that you can use Replikanto Local Network Mode for copying the trades between the multiple VPS, so the trades copy between different Rithmic prop firms and accounts.
Tradovate prop accounts are easier in that you can be logged into multiple Tradovate accounts from different prop firms on the same VPS, whereas with Rithmic you'd need a VPS for each prop firm. However there are some prop firms that only have Rithmic accounts for NinjaTrader such as Earn2Trade and TopStep, so there's always an option available for copying trades with all prop firms, both Rithmic and Tradovate style.