From Tony H Ver 1

study("Twin Hull Crossover (TH)",overlay=true)

LowestPeriod = input(title="Lowest Period",type=integer,defval=8)
MediumPeriod = input(title="Medium Period",type=integer,defval=10)

LowestEMA = wma(2 * wma(src, len / 2) - wma(src, len), round(sqrt(len)))
MediumEMA = ema(close,MediumPeriod)

//LowestEMA = ema(close,LowestPeriod)
//MediumEMA = ema(close,MediumPeriod)

LEColor = LowestEMA > LowestEMA[1] ? green : red
MEColor = MediumEMA > MediumEMA[1] ? lime : maroon

plot( LowestEMA, color= LEColor , title="Lowest EMA", trackprice=false, style=line)
plot( MediumEMA ,color= MEColor , title="Medium EMA", trackprice=false, style=line)

Trend = LowestEMA > MediumEMA ? 1 : LowestEMA < MediumEMA ? -1 : 0
plotarrow(Trend == 1 and Trend[1] != 1 ? Trend : na, title="Up Entry Arrow", colorup=lime, maxheight=30, minheight=20, transp=0)
plotarrow(Trend == -1 and Trend[1] != -1 ? Trend : na, title="Down Entry Arrow", colordown=red, maxheight=30, minheight=20, transp=0)