Oxtoby told BBC Sport NI that her preparations for the encounters with Croatia would include speaking with her Wales counterpart Rhian Wilkinson, after the Welsh finished top of the qualifying group which included the Croatians.
“I’ll be in touch [with the Wales head coach] for some tips, but we’re getting to work right now in terms of what we need to know,” explained the Australian former Chelsea assistant coach.
“We have a pretty stringent process we go through in terms of our opposition analysis so the guys will be working away to make sure we’ve got all the information we need to give ourselves every opportunity we need to be successful.
“Playing away from home first is always a challenge so we’ll try and get ourselves based where we can get some good work in beforehand and focus on us and be ready for the game.”
Oxtoby’s team sit 48th in the Fifa rankings, eight places above Croatia, while 16th-ranked Norway will be favourites to overcome Albania and stand in the way of Northern Ireland potentially reaching a second European Championship should they advance at the expense of the Croatians.
“The pressure of a play-off and all that comes with it, I don’t think rankings really come into it,” said Oxtoby.
“It’s about making sure you can execute on the day across the two ties so that’s what we need to be focused on, and ourselves more importantly, continuing our journey.
“We’ll focus on this first round and then concentrate on the next round if we get there.”
The round two play-offs will be played on 27 November and 3 December.