In pathfinder 1 I used to sent my eidolon to scout. We communicated via message spell. The worst scenario was, that he disappearead for one day.
Or somebody had figmemt familiar - same concept.
Or dedicated rouge (or investigator) with dampen presence (against blindsight), invisibility ring, pull ring of scentand wings of flying (against tremorsense) combined with magic aure (against detect magic and arcane sight).
Is there some easy way to scout reliably in Pathfinder 2?
Also, it's very easy to multiclass to get all the Invisibility, Fly and Dimension Door spells. Multiclass into Bard, Wizard or Sorcerer and you get all of them (it's still 3 feats to get Fly/Dimension Door, but you get other things also).
So, in my opinion, lots of characters can do it, nearly all in fact. I think it's the good point of PF2, nothing is really limited to one class.
You can also use your Familiar or your Animal Companion to scout, but you have to wait for it to come back and report.
Safe is relative, but anyone who invests in sufficient stealth can sneak along decently enough. Rogue is probably the best, possibly with something to provide invisibility when things get bad. Your GM might allow you to send your familiar/animal out to scout, though they might decide the encounter mode rules imply that familiars/animal companions are useless without supervision at all times.