You risk having cross-currents such that a slightly higher winding voltage from one transformer sends current into the winding of other transformer.
Take each transformer and use an ordinary rectifier bridge for each transformer. Then join the rectified voltages at the output of the two bridge rectifiers. Then, the risk of cross-currents is eliminated.
To parallel connect transformer secondaries, you need identical transformers with the same part number and made in the same time period.
Thank you so much. They are definitely not identical. I was just trying to save some currency.
Your voltage and current levels are different but the connections are the same. The load-sharing will not be 100% but you can at least get 4A out.
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The particular danger here is that the winding counts or arrangements may differ between transformers. You can check this by measurements of secondary voltage difference however - combine that difference with the winding resistances to determine if the unwanted current is significant (50mA wouldn't matter here, 1A would).