The white flag is free.
Once that's used, any further personal flags will need to replace existing ones. My suggestions, in no particular order, are:.
. The British red and blue ensigns in "perflg3" - if you want to fly a British flag, use the actual British flag for your chosen period;
. The one which looks like a mutated British flag in "perflg4". It's actually a Russian naval jack, and jack flags are special ones which should only be flown from a jackstaff, and then only when moored. The proper Russian naval ensign is a simple blue saltire on white background which is in "perflg3", so the jack is both incorrect and redundant;
. The one with red and white stripes and a snake with the motto "Don't Tread on Me" in "perflg5". This is the American "First Navy Jack", which means that like the Russian jack, it should only be flown on a jackstaff, in port; and like Britain, if you want to fly an American flag, use an actual American flag.
And ideally, if you can get "Woodes Rogers" to use the Swedish national flag, the copy in "perflg5" could be replaced too.