IMO, you have got yourself two pretty good SF prospects. the two 18 years old 6'8.
if i were you, i will still choose to start on one position training to make those two into SFs starting with OD training.
long term, if you decide to sell both SF, you will get tons of money. probably around 2 seasons when they are 20 years old and with a real good foundation of SF skillset. they can get you around 3m.
is up to you though, just an advice