rav4 2L diesel, 2002, engine failure

The diesel engine in the XA20 RAV4 is the 1CD-FTV (marketed as "2.0 D-4D") - the same basic block was used in the E120 Corolla (exact model years depend on your location - it started in Japan in 2000 but came later to some markets IIRC) and both are built on the same basic platform - Toyota's "MC" platform so that makes it reasonably likely that you can do such a swap.

The Avensis used the 1CD-FTV as well (until '09) in some of the cars - however some of the second generation Avensis cars had the 1AD-FTV instead. So it would be advisable to check carefully! I think they started using that ~2005 so cars before that should be the right engine.

2nd generation (03-09) Avensis cars are also built on the MC platform.

I must stress that this isn't a swap I've seen done personally so I don't know for sure that it's doable - would have to check part numbers for that and without the frame numbers of the recipient and donor that's a needle in a stack of needles.