If you Trying Just copy the Property Value To Share The Value, That Can't Be Done Unless That Value Is A Third Handle Class
classdef ByRefProp < handle
properties
value;
end
end
Now you Can Set
x = X(); y = Y();
y.a = ByRefValue();
x.a = y.a;
y.a.value = 'The Quick Brown Fox Jumps Over The Lazy Dog';
disp(x.a.value);
More importantly, You Should Consider The Relationship Between X and Y.
You May Need One To Contain Or Inherit The Other.
