Internal txn support

Hi - two related questions:

1/ is it possible to access internal txn data from w/i a subgraph handler?
2/ if not, is this capability on the roadmap today? if so, where can I learn more about it?

I believe the answer to 1/ is no but wish to confirm. (Perused docs, gh issues, forum, discord).

Thanks

following up on my own q here, some networks indeed have access to callHandlers: Creating a Subgraph | Docs | The Graph

unclear if there are plans to help expand to more networks. Seems like blocked by external support based on the below

Call handlers currently depend on the Parity tracing API and these networks do not support it.