Steps to reproduce on regtest:

```
converttopsbt 02000000000101ab73dba46508bacdb49a988ddd74bc9d39c9cb7e057af060ca8c6b6861e28e3c0300000000feffffff02b828d0b20000000017a914d1954862afd728fbb055149002958e1d1b9e1f0b8700ca9a3b0000000017a91442170ccb3441cff1723af9afab6f2553103e1d578702473044022077380c6e16496d9905aef120694c329be51522847cb5d53fa74b94698c95678d02202d32c46e0e17420a83dee830fefda7d40529182f5d82be47c2b49a7b83214ab50121026d483d6628dcc3ef6e3ab9ed4937c452c263c7e0ac80eb4be97426d5da8f640500000000
```
or 
```
converttopsbt 02000000000101ab73dba46508bacdb49a988ddd74bc9d39c9cb7e057af060ca8c6b6861e28e3c0300000000feffffff02b828d0b20000000017a914d1954862afd728fbb055149002958e1d1b9e1f0b8700ca9a3b0000000017a91442170ccb3441cff1723af9afab6f2553103e1d578702473044022077380c6e16496d9905aef120694c329be51522847cb5d53fa74b94698c95678d02202d32c46e0e17420a83dee830fefda7d40529182f5d82be47c2b49a7b83214ab50121026d483d6628dcc3ef6e3ab9ed4937c452c263c7e0ac80eb4be97426d5da8f640500000000 false
```

Further reading: #13738
int change_position;
    CMutableTransaction rawTx = ConstructTransaction(request.params[0], request.params[1], request.params[2], request.params[3]["replaceable"]);
    FundTransaction(pwallet, rawTx, fee, change_position, request.params[3]);
    
    PartiallySignedTransaction psbtx(rawTx);
    
    bool bip32derivs = request.params[4].isNull() ? false : request.params[4].get_bool();
    bool complete = true;
    const TransactionError err = FillPSBT(pwallet, psbtx, complete, 1, false, bip32derivs);
    if (err != TransactionError::OK) {
        throw JSONRPCTransactionError(err);
    }
    
    CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
    ssTx << psbtx;
    UniValue result(UniValue::VOBJ);
    result.pushKV("psbt", EncodeBase64(ssTx.str()));
    result.pushKV("fee", ValueFromAmount(fee));
    result.pushKV("changepos", change_position);
    return result;
}
UniValue abortrescan(const JSONRPCRequest& request); 
UniValue dumpprivkey(const JSONRPCRequest& request); 
UniValue importprivkey(const JSONRPCRequest& request);
UniValue importaddress(const JSONRPCRequest& request);
UniValue importpubkey(const JSONRPCRequest& request);
UniValue dumpwallet(const JSONRPCRequest& request);
UniValue importwallet(const JSONRPCRequest& request);
UniValue importprunedfunds(const JSONRPCRequest& request);
UniValue removeprunedfunds(const JSONRPCRequest& request);