Steps to reproduce on regtest:

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

Further reading: #13738
{
    const RPCHelpMan help{"testmempoolaccept",
                "\nReturns result of mempool acceptance tests indicating if raw transaction (serialized, hex-encoded) would be accepted by mempool.\n"
                "\nThis checks if the transaction violates the consensus or policy rules.\n"
                "\nSee sendrawtransaction call.\n",
                {
                    {"rawtxs", RPCArg::Type::ARR, RPCArg::Optional::NO, "An array of hex strings of raw transactions.\n"
            "                                        Length must be one for now.",
                        {
                            {"rawtx", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, ""},
                        },
                        },
                    {"maxfeerate", RPCArg::Type::AMOUNT,  FormatMoney(DEFAULT_MAX_RAW_TX_FEE), "Reject transactions whose fee rate is higher than the specified value, expressed in " + CURRENCY_UNIT + "/kB\n"},
                },
                RPCResult{
            "[                   (array) The result of the mempool acceptance test for each raw transaction in the input array.\n"
            "                            Length is exactly one for now.\n"
            " {\n"
            "  \"txid\"           (string) The transaction hash in hex\n"
            "  \"allowed\"        (boolean) If the mempool allows this tx to be inserted\n"
            "  \"reject-reason\"  (string) Rejection string (only present when 'allowed' is false)\n"
            " }\n"
            "]\n"
                },
                RPCExamples{
            "\nCreate a transaction\n"
            + HelpExampleCli("createrawtransaction", "\"[{\\\"txid\\\" : \\\"mytxid\\\",\\\"vout\\\":0}]\" \"{\\\"myaddress\\\":0.01}\"") +
            "Sign the transaction, and get back the hex\n"