In general, the answer is no.
In practice, the answer is...sort of, but not really, and definitely not as well. If it's possible it will be via feats and/or paragon paths.
For the specific cases you've mentioned:
With the ranger, the only class feature of archery style is the Defensive Mobility bonus feat. So in this case, if you play a Two weapon ranger, and take Defensive Mobility you've technically gained the class feature. However, you would not qualify as an Archery Style ranger to, say, qualify for the paragon paths that requires it (namely Battlefield Archer). Going the other direction, you can take Toughness as a feat, but you can't really replace the class feature allowing you to wield one handed weapons in your off hand (there could be a PP that does it, but I'm not aware of one and a cursory search of the compendium did not reveal one).
The Rogue is a bit tougher. As pointed out in the comments, in Epic you can pick up a second Rogue Talent with the feat Versatile Rogue. The three class features (Rogue Talents) you listed are the following, if it's possible to replicate the results in another manner I've included the method:
- CHA mod to opportunity attacks.
- Depending on how high your CHA mod is, this could be replaced by Devensive Mobility.
- easier hiding, lower movement penalty to stealth
- The Sneak's trick utility power allows this to some degree. But it's a power for the Thief and not available to a Scoundrel rogue. There are a couple of encounter utilities that also provide similar benefits, taking those would provide similar benefits to this class feature.
- STR mod to SA damage
-This one simply isn't replicable via any means.
With the methods I've listed above you won't qualify for the riders, but with the epic feat you will.
4e classes are designed for the most part to be pretty compartmentalized and dipping into other class features is in general not supported. There are some cases where it's possible (especially in cases where the feature provides a bonus feat or something that can be replicated with a feat), but they are going to be epic level feats and by that time you may not have the flexibility to properly utilize them.
So the long and short is that you can rarely just grab another class feature, but more often you can replicate the functionality.