Well, I took inspiration from NinjaTrader’s native horizontal line code and simply added a price display. It adapts to the tick size of the instrument you choose. It’s extremely basic, but I hope it helps! I apologize for any inconvenience! Thank you 
User Submitted App Features: NinjaTrader 8 Compatible
BarBigTrade
BarBigTrade is an order-flow marker indicator designed to detect large single prints and optional sweep behavior, and place those events directly on the related bar and price level. It can separate buy and sell side large trades, optionally detect sweeps, scale marker size by traded volume, and trigger alerts, making it useful for spotting aggressive initiative, absorption, and liquidity sweeps.