Converting RSRD abilities to Echelon talents is usually pretty straightforward.
Many abilities in D&D 3.x are built up of smaller abilities, usually along a path of some sort. Feat paths are pretty obvious (weapon focus and weapon specialization are an example, as is the Mobility feat path leading to Whirlwind Attack, though that’s a short one). Various class abilities improve as a character takes levels in the class (evasion leads to improved evasion, similarly with uncanny dodge, and so on). It isn’t really implemented in D&D 3.x, but it’s not unreasonable to treat access to spells and magic as a path, where knowledge of high-level spells of a particular type implies knowledge of lower-level spells of the same or similar type (if you can cast meteor swarm, it’s reasonable to expect that you can cast fireball… even if D&D 3.x RAW actually doesn’t require or enforce this in any way).