Actually, now I am a bit confused about the scope of this bounty and #32.
@skilesare Did we want to do this as this would mean that I make inter-canister calls from my library?
In #32, it is mentioned that we want to avoid async calls to a utility canister and the library from #32 is supposed to use this library for signing transactions. So if this library makes inter-canister calls, then how would the library from #32 avoid them? 
See Open: ICDevs.org - Bounty #32 - EVM Transactions - Motoko - $8,000 - #16 by darkdrag00n