Here I simply show the results of a sum of Bernoulli random variables where there is noise added to the probability parameter that follows a truncated Gaussian distribution, restricted to valid values of the parameter.
Let's assume we have a random variable $X$ which is, conditionally, a Bernoulli random variable.
$$X | \epsilon\sim\text{Bern}(p+\epsilon)$$
where
$$\epsilon\sim TN(0,\sigma,a=0,b=1)$$
and $0<p<1$, $\sigma>0$ and $(a,b)$ represent the lower and upper truncation levels of the truncated Normal distribution, respectively. The truncated Normal distribution is used to ensure that the Bernoulli probability parameter is bounded between valid values.
We can simplify the above characterisation slightly as
\begin{align}
X | \epsilon\sim&\text{Bern}(\epsilon)\notag
\end{align}
where
\begin{align}
\epsilon\sim&TN(p,\sigma,a=0,b=1)\notag
\end{align}
We can derive the probability mass function of $X$ using
\begin{align}
p_{X}(x)&=\int_{\epsilon}p_{X | \epsilon}(x | \epsilon)\, p_{\epsilon}(\epsilon)\,d\epsilon \notag
\end{align}
where
\begin{align}
p_{X | \epsilon}(x | \epsilon)&=\epsilon^{x}(1-\epsilon)^{1-x}\notag\\
&=\epsilon x+(1-\epsilon)(1-x)\notag
\end{align}
and
\begin{align}
p_{\epsilon}(\epsilon)&=\frac{e^{-\frac{1}{2}\big(\frac{\epsilon-p}{\sigma}\big)^{2}}}{\sqrt{2\pi}\sigma\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)}\notag\\
&=Ae^{-\frac{1}{2}\big(\frac{\epsilon-p}{\sigma}\big)^{2}}\notag
\end{align}
So
\begin{align}
p_{X}(x)&=\int_{0}^{1}[\epsilon x+(1-\epsilon)(1-x)]Ae^{-\frac{1}{2}\big(\frac{\epsilon-p}{\sigma}\big)^{2}}\,d\epsilon \notag
\end{align}
Let
\begin{align}
z=\epsilon-p\notag
\end{align}
Then
\begin{align}
dz=d\epsilon\notag
\end{align}
\begin{align}
p_{X}(x)&=\int_{-p}^{1-p}[(z+p)x+(1-z-p)(1-x)]Ae^{-\frac{1}{2}\big(\frac{z}{\sigma}\big)^{2}}\,dz \notag\\
&=\int_{-p}^{1-p}[px+(1-p)(1-x)]Ae^{-\frac{1}{2}\big(\frac{z}{\sigma}\big)^{2}} +(2x-1)zAe^{-\frac{1}{2}\big(\frac{z}{\sigma}\big)^{2}}\,dz \notag\\
&=px+(1-p)(1-x)+(2x-1)A\Big[-\sigma^{2}\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)\Big]\notag
\end{align}
Which gives
$$
p_{X}(x)=
\left\{
\begin{aligned}
(1-p) + \frac{\sigma\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)}{\sqrt{2\pi}\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)} &\quad\quad x=0\\
p - \frac{\sigma\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)}{\sqrt{2\pi}\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)} &\quad\quad x=1
\end{aligned}
\right.
$$
We can confirm this is a valid probability mass function by
\begin{align}
\sum_{x}p_{X}(x)&=p_{X}(x=0)+p_{X}(x=1)\notag\\
&=(1-p)+\frac{\sigma\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)}{\sqrt{2\pi}\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)}\notag\\
&\quad+p-\frac{\sigma\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)}{\sqrt{2\pi}\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)}\notag\\
&=1\notag
\end{align}
Thus, we can say that
\begin{align}
X\sim\text{Bern}(p^{*})\notag
\end{align}
where
\begin{align}
p^{*}&=p-\frac{\sigma\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)}{\sqrt{2\pi}\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)}\notag
\end{align}
We can see that
\begin{align}
\lim_{\sigma \to 0} \frac{\sigma\Big(e^{-\frac{1}{2}\big(\frac{1-p}{\sigma}\big)^{2}}-e^{-\frac{1}{2}\big(\frac{p}{\sigma}\big)^{2}}\Big)}{\sqrt{2\pi}\big(\Phi(1;p,\sigma)-\Phi(0;p,\sigma)\big)}=0\notag
\end{align}
which implies that as $\sigma \to 0$, the Bernoulli with Gaussian noise converges to a Bernoulli without noise, as expected. Furthermore, for $p=0.5$, the distribution of a Bernoulli with Gaussian noise is the same as that of a Bernoulli without noise.
Extension to the Binomial distribution is simple. Let's assume we have a sequence of $n$ independent Bernoulli trials with parameter $p^{*}$ and we define the sum as
\begin{align}
S_{n}&=\sum_{i=1}^{n}X_{i}\notag
\end{align}
The moment generating function (MGF) of $S_{n}$ is
\begin{align}
M_{S_{n}}(t)&=(M_{X}(t))^n=(1-p^{*}+p^{*}e^{t})^{n}\notag
\end{align}
which is the MGF of a $\text{Binomial}(n,p^{*})$ random variable.
Example
We can illustrate the above with an example:
$$p=\{0.3,0.7\},\, \sigma=0.5,\, n=20$$
where $n$ is the number of independent Bernoulli trials.
This gives
$$p^{*}=\{0.442248,0.557752\}$$
The probability mass functions of the resultant Binomial random variables with and without noise are shown below.
